Answer:
36
Step-by-step explanation:
formula of area for square:
A=s^2
s=6
A=6^2
A=36
Answer:
36
Step-by-step explanation:
I got it right
Which equation best describes the graph.
Answer:
A. [tex]y=4x-5[/tex]
Step-by-step explanation:
The equations are in slope-intercept form, which is written as y=mx+b. Where m is the slope and b is the y-intercept. So, first, find the slope. The line increases by 4 every unit; this means the slope is 4. Then, find the y-intercept. The y-intercept is where the line crosses the y-axis. Since the line crosses at -5, that is the b value. Therefore, the final answer is y=4x-5.
An entry in the Peach Festival Poster Contest must be rectangular and have an area of 1200 square inches. Furthermore, it's length must be 20 inches longer than it's width. Find the dimensions.
Answer:
The length is 46.05551275 inches, and the width is 26.05551275 inches.
Step-by-step explanation:
We know that the area must be 1200 square inches. Using this information, we can create an equation, where x is length and y is width:
x*y=1200
We know that its length must be 20 inches longer than its width. Therefore, x=y+20. Using this new information, we can replace 'x' in 'x*y=1200' with 'y+20':
(y+20)*y=1200
[tex]y^{2} +20y=1200[/tex]
[tex]y^{2} +20y-1200=0[/tex]
I have decided to use the quadratic formula, but you could also factor this equation into the 'intercept' form to determine the roots, which ultimately provides the same answer.
[tex]y=\frac{-b+\sqrt{b^{2} -4ac} }{2a}[/tex]
[tex]y=\frac{-(20)+\sqrt{(20)^{2} -4(1)(-1200)} }{2(1)}[/tex]
[tex]y=\frac{-(20)+\sqrt{400+4800} }{2}[/tex]
[tex]y=\frac{-(20)+\sqrt{5200} }{2}[/tex]
[tex]y=\frac{52.11102551 }{2}[/tex]
[tex]y=26.05551275[/tex] inches
[tex]x=y+20[/tex]
[tex]x=(26.05551275)+20[/tex]
[tex]x=46.05551275[/tex] inches
Therefore, the length is 46.05551275 inches, and the width is 26.05551275 inches.
HELP ASAP
The figure shows two parallel lines AB and DE cut by the transversals AE and BD.
Which best explains the relationship between triangle ABC and triangle EDC?
Answer
its the first one
Step-by-step explanation:
A tank is filled at a constant rate. 10 minutes after filling is started, the tank contains 4.8L of water. After 35 minutes the tank contains 7.3L of water.
a. Find the rate at which the tank is being filled?
b. Find the initial volume of fluid in the tank and express it as a function in terms of V and t.
c. Find how long it takes to filled, if the tank has a maximum capacity of 60L?
Answer:
Part A)
0.1 liters per minute.
Part B)
There was initially 3.8 liters of water.
[tex]\displaystyle V(t) = 0.1(t - 10) + 4.8[/tex]
Part C)
562 minutes.
Step-by-step explanation:
A tank is filled at a constant rate. After 10 minutes, the tank contains 4.8 L of water and after 35 minutes, the tank contains 7.3 L of water.
Part A)
We can represent the current data with two points: (10, 4.8) and (35, 7.3). The x-coordinate is measured in minutes since the tank began to be filled and the y-coordinate is measured in how full the tank is in liters.
To find the rate at which the tank is being filled, find the slope between the two points:
[tex]\displaystyle m = \frac{\Delta y}{\Delta x} = \frac{(7.3)-(4.8)}{(35)-(10)} = \frac{2.5}{25} = 0.1[/tex]
In other words, the rate at which the tank is being filled is 0.1 liters per minute.
Part B)
To find the function of the volume of the tank, we can use the point-slope form to first find its equation:
[tex]\displaystyle y - y_1 = m( x - x_1)[/tex]
Where m is the slope/rate of change and (x₁, y₁) is a point.
We will substitute 0.1 for m and let (10, 4.8) be the point. Hence:
[tex]\displaystyle y - (4.8) = 0.1(x - 10)[/tex]
Simplify:
[tex]\displaystyle y = 0.1(x-10) + 4.8[/tex]
Since y represent how full the tank is and x represent the time in minutes since the tank began to be filled, we can substitute y for V(t) and x for t. Thus, our function is:
[tex]\displaystyle V(t) = 0.1(t - 10) + 4.8[/tex]
The initial volume is when t = 0. Evaluate:
[tex]\displaystyle V(0) = 0.1 ((0) - 10) + 4.8 = 3.8[/tex]
There was initially 3.8 liters of water.
Part C)
To find how long it will take for the tank to be completely filled given its maximum capacity of 60 liters, we can let V(t) = 60 and solve for t. Hence:
[tex]60 = 0.1(t - 10) + 4.8[/tex]
Subtract:
[tex]55.2 = 0.1(t - 10)[/tex]
Divide:
[tex]552 = t - 10[/tex]
Add. Therefore:
[tex]t = 562\text{ minutes}[/tex]
It will take 562 minutes for the tank to be completely filled.
Martin currently has a balance of $948 in an account he has held for 20 years. He opened the account with an initial deposit of $600. What is the simple interest on the account?
A - 1.8%
B - 2.9%
C - 3.2%
D - 7.9%
If f(x)=3x^2-x+6, evaluate f(-4)
Answer:
f(-4) = 58
Step-by-step explanation:
Let x = -4:
[tex]f(-4)=3(-4)^2-(-4)+6\\\\f(-4)=3(16)+4+6\\\\f(-4)=48+4+6\\\\f(-4)=58[/tex]
Help us plazz this is mathematics IGCSE fast as you can
Answer:
Step-by-step explanation:
y varies direcrtly with √(x+5) wich can be expressed mathematically as:
● y = k*√(x+5)
Let's calculate k khowing that y=4 and x=-1
● 4 = k*√(-1+5)
● 4 = k*√(4)
● 4 = k * 2
● k = 4/2
● k = 2
■■■■■■■■■■■■■■■■■■■■■■■■■■
Let's calculate y khowing that x = 11
● y = k*√(x+5)
● y = 2×√(11+5)
● y = 2× √(16)
● y = 2× 4
● y = 8
Answer:
The value of y is 8.
Step-by-step explanation:
Given that y is directly proportional to √(x+5) so the equation is y = k√(x+5) where k is constant. First, you have to find the value of k with given values :
[tex]y = k \sqrt{x + 5} [/tex]
[tex]let \: x = - 1,y = 4[/tex]
[tex]4 = k \sqrt{ - 1 + 5} [/tex]
[tex]4 = k \sqrt{4} [/tex]
[tex]4 = k(2)[/tex]
[tex]4 \div 2 = k[/tex]
[tex]k = 2[/tex]
So the equation is y = 2√(x+5). In order to find the value of y, you have to substitute x = 11 into the equation :
[tex]y = 2 \sqrt{x + 5} [/tex]
[tex]let \: x = 11[/tex]
[tex]y = 2 \sqrt{11 + 5} [/tex]
[tex]y = 2 \sqrt{16} [/tex]
[tex]y = 2(4)[/tex]
[tex]y = 8[/tex]
The radius of a circle measures 5 inches A central angle of the circle measuring 12 radians cuts off a sector
What is the area of the sector?
Enter your answer as a simplified fraction in the box
area =
inches squared
Answer:
25/4 square inches
Step-by-step explanation:
The area of a sector of a circle is given by the formula ...
A = (1/2)r²θ
where r is the radius and θ is the central angle in radians.
For your sector, the area is ...
A = (1/2)(5 in)²(1/2) = 25/4 in²
A clothing factory makes small, medium, and large sweaters. Last week, the factory made
1,612 sweaters. The factory made 3 times as many small sweaters as large sweaters. They
made 3 times as many medium sweaters as small sweaters.
How many small sweaters did the factory make last week?
This requires finding the number of small sweaters the company made last week
Number of small sweaters the company produced last week is 372
Total sweaters made = 1,612
Let
Small sweaters = 3x
Medium sweaters = x
Large sweaters = 3(3x) = 9x
Total = small + medium + large
1,612 = 3x + x + 9x
1612 = 13x
Divide by 13
x = 1612/13
Medium sweaters = x = 124
Small sweaters = 3x
= 3(124)
= 372
Read more:
https://brainly.com/question/24326559
PLEASE HELP FAST!! The cone and the cylinder below have equal surface area. True or False??
Answer:
B. FALSE
Step-by-step explanation:
Surface area of cone = πr(r + l)
Where,
r = r
l = 3r
S.A of cone = πr(r + 3r)
= πr² + 3πr²
S.A of cone = 4πr²
Surface area of cylinder = 2πrh + 2πr² = 2πr(h + r)
Where,
r = r
h = 2r
S.A of cylinder = 2πr(2r + r)
= 4πr² + 2πr²
S.A of cylinder = 6πr²
The surface are of the cone and that of the cylinder are not the same. The answer is false.
Answer:false
Step-by-step explanation:
False
12. Consider the function ƒ(x) = x^4 – x^3 + 2x^2 – 2x. How many real roots does it have?
options:
A) 2
B) 1
C) 3
D) 4
Answer:
Step-by-step explanation:
Hello, let's factorise as much as we can.
[tex]x^4-x^3 + 2x^2-2x\\\\=x(x^3-x^2+2x-2)\\\\=x(x-1)(x^2+2)[/tex]
So, the solutions are
[tex]0, \ 1, \ \sqrt{2}\cdot i, \ -\sqrt{2}\cdot i[/tex]
There are only 2 real roots.
Thank you.
Answer:
So, the solutions are
There are only 2 real roots.
Step-by-step explanation:
(All yes or no questions). Determine whether each of the following pairs of angles have equal measures:
a. KJLand LJM
b. MJP and PJR
C. LJP and NJR
d. MJK and PJR
9514 1404 393
Answer:
a) no
b) yes
c) yes
d) no
Step-by-step explanation:
Angle LJM is complementary to KJL, so is ...
angle LJM = 90° -42° = 48°
Angle NJP is marked as congruent to angle PJQ, so is also 48°.
__
a) ∠KJL = 42° ≠ 48° = ∠LJM . . . . NO
b) ∠MJP = 46°+48° = 48° +46° = ∠PJR . . . . YES
c) ∠LJP = 48° +46° +48° = 48° +48° +46° = ∠NJR . . . . YES
d) ∠MJK = 90° ≠ 48° +46° = ∠PJR . . . . NO
2
Select the correct answer.
which number is the additive Inverse of -10 ?
O A 10 1
Ос. о
OD. -41
Reset
Next
Answer:
[tex]\boxed{\sf 10}[/tex]
Step-by-step explanation:
The additive number of any number is the number when added to the number gives a result of zero.
So, if we add 10 to -10 we get a result of zero.
=> -10+10
=> Zero
An architect was designing a rectangular room with a length of 16 feet, a width of 14 feet,
and a height of 10 feet.
What is the volume, in cubic feet of the room?
Show your work
cubic feet
Answer
The architect changed his design and added 2 feet to the length and width of the room.
In cubic feet, how much greater is the volume of the room in his new design?
Show your work
cubic feet
Answer
Hurrryyy knowww
Answer:
(1) 16 x 14 x 10 Room: 2240 ft^3.
(2) How much greater the 18 x 16 x 10 Room is: 640 ft^3.
Step-by-step explanation:
To find the volume of a given space, all we need to do is multiply length*width*height. In this case, the values are 16*14*10, which equals 2240 ft^3.
The changed design would have a volume of 18*16*10, which would equal 2880 ft^3.
To find the difference in volume between the two rooms, all we have to do is subtract the smaller room from the bigger room. 2880 - 2240 = 640 ft^3.
Find the area of the figure. (Sides meet at right angles.)
Answer:
56
Step-by-step explanation:
A=(3*4)+(4*(4+3+4))=56
What is the value of x that makes l1||l2?
A. 15
B. 25
C. 18
D. 29
Answer:
x = 29
Step-by-step explanation:
The angles are corresponding angles and corresponding angles are equal when the lines are parallel
3x+17 = 4x-12
Subtract 3x from each side
3x+17-3x = 4x-12-3x
17 = x-12
Add 12 to each side
17+12 = x-12+12
29 =x
Answer:
D. 29
Step-by-step explanation:
If you plug in 29 in the missing values for L1 and L2, you get
L1 = 3(29) + 17 = 104
L2 = 4(29) - 12 = 104
I know I am correct because since both L1 and L2 are parallel and T in cutting them, I know that they are both going to be the same degrees, 104.
So, your answer would be D. 29
Hope the helps! :)
What is the distance between the coordinates (4,2) and (0,2)
Answer: Hi!
The distance between the coordinates (4,2) and (0,2) is 4 units.
The coordinates have the same location on the y axis, but the coordinates have different locations on the x axis. (4,2) is 4 units to the right of the x axis and 2 up on the y axis, while (0,2) goes just straight up to 2 on the y axis. If we graphed these, the two points would be aligned with each other, but a distance of 4 units would separate them horizontally.
Hope this helps!
point estimate A sample of 81 observations is taken from a normal population with a standard deviation of 5. The sample mean is 40. Determine the 95% confidence interval for the population mean
Answer:
The 95 percent Confidence Interval is for the population is (38.911 , 41.089)
Step-by-step explanation:
To solve the above question, we would be making use of the confidence interval formula:
Confidence Interval = Mean ± z score × σ/√n
In the above question,
Mean = 40
σ = Standard deviation = 5
n = number of samples = 81
Confidence Interval = 95%
The z score for a 95% confidence interval = 1.96
Therefore, the confidence interval =
= 40 ± 1.96 (5/√81)
= 40 ± 1.96(5/9)
= 40 ± 1.0888888889
Confidence Interval
a)40 + 1.0888888889
= 41.0888888889
Approximately = 41.089
b ) 40 - 1.0888888889
= 38.911111111
Approximately = 38.911
Therefore, the 95 percent Confidence Interval is for the population is (38.911 , 41.089)
the height of a soccer ball that is kicked from the ground can be approximated by the function:
y = -12x^2 + 60x
where y is the height of the soccer ball in feet in x seconds after it is kicked. Find the time, in seconds, it takes from the moment soccer is kicked until it returns to the ground
Answer:
5 seconds
Step-by-step explanation:
Well we know that when the soccer ball is on the ground the height will be 0.
So we replace y with 0 and solve for x.
0=-12x²+60x
factor out and divide x, (this x is x=0, which is before he kicked it)
0=-12x+60
subtract 60 from both sides
-60=-12x
x=5
-3x^5y^7/6xy^8
PLEASE HELP
9514 1404 393
Answer:
-x^4/(2y)
Step-by-step explanation:
Perhaps you want to simplify ...
[tex]-\dfrac{3x^5y^7}{6xy^8}=-\dfrac{3}{6}x^{5-1}y^{7-8}=-\dfrac{x^4y^{-1}}{2}=\boxed{-\dfrac{x^4}{2y}}[/tex]
__
The applicable rules of exponents are ...
(a^b)/(a^c) = a^(b-c)
a^-b = 1/a^b
_____
Comment on notation
When writing a fraction in plain text, any denominator that includes an arithmetic operation must be enclosed in parentheses. Your given expression is properly written as ...
-3x^5y/(6xy^8)
Without the parentheses, the product xy^8 is in the numerator. This is demanded by the order of operations, which requires you evaluate your expression as (-3x^5y^7/6)·xy^8
Rawen buys 5 1/4 yards of fabric. Zoey buys 2/3 as much fabric as Rawen does. How much fabric does Zoey buy?
Answer:
3.5 yards of fabric
Step-by-step explanation:
Find 2/3 of 5 1/4:
5 1/4(2/3)
= 3.5 yards of fabric
Express the product of z1 and z2 in standard form given that [tex]z_{1} = -3[cos(\frac{-\pi }{4} )+isin(\frac{-\pi }{4} )][/tex] and [tex]z_{2} = 2\sqrt{2} [cos(\frac{-\pi }{2} )+isin(\frac{-\pi }{2} )][/tex]
Answer:
Solution : 6 + 6i
Step-by-step explanation:
[tex]-3\left[\cos \left(\frac{-\pi }{4})\right+i\sin \left(\frac{-\pi }{4}\right)\right]\cdot \:2\sqrt{2}\left[\cos \left(\frac{-\pi }{2}\right)+i\sin \left(\frac{-\pi }{2}\right)\right][/tex]
This is the expression we have to solve for. Now normally we could directly apply trivial identities and convert this into standard complex form, but as the expression is too large, it would be easier to convert into trigonometric form first ----- ( 1 )
( Multiply both expressions )
[tex]-6\sqrt{2}\left[\cos \left(\frac{-\pi }{4}+\frac{-\pi \:\:\:}{2}\right)+i\sin \left(\frac{-\pi \:}{4}+\frac{-\pi \:\:}{2}\right)\right][/tex]
( Simplify [tex]\left(\frac{-\pi }{4}+\frac{-\pi }{2}\right)[/tex] for both [tex]\cos \left(\frac{-\pi }{4}+\frac{-\pi }{2}\right)[/tex] and [tex]i\sin \left(\frac{-\pi }{4}+\frac{-\pi }{2}\right)[/tex] )
[tex]\left(\frac{-\pi }{4}+\frac{-\pi }{2}\right)[/tex] = [tex]\left(-\frac{3\pi }{4}\right)[/tex]
( Substitute )
[tex]-6\sqrt{2}\left(\cos \left(-\frac{3\pi }{4}\right)+i\sin \left(-\frac{3\pi }{4}\right)\right)[/tex]
Now that we have this in trigonometric form, let's convert into standard form by applying the following identities ----- ( 2 )
sin(π / 4) = √2 / 2 = cos(π / 4)
( Substitute )
[tex]-6\sqrt{2}\left(-\sqrt{2} / 2 -i\sqrt{2} / 2 )[/tex]
= [tex]-6\sqrt{2}\left(-\frac{\sqrt{2}}{2}-\frac{\sqrt{2}}{2}i\right)[/tex] = [tex]-\frac{\left(-\sqrt{2}-\sqrt{2}i\right)\cdot \:6\sqrt{2}}{2}[/tex]
= [tex]-3\sqrt{2}\left(-\sqrt{2}-\sqrt{2}i\right)[/tex] = [tex]-3\sqrt{2}\left(-\sqrt{2}\right)-\left(-3\sqrt{2}\right)\sqrt{2}i[/tex]
= [tex]3\sqrt{2}\sqrt{2}+3\sqrt{2}\sqrt{2}i:\quad 6+6i[/tex] - Therefore our solution is option a.
Given two points M & N on the coordinate plane, find the slope of MN , and state the slope of the line perpendicular to MN . (there's two questions)
1) M(9,6), N(1,4)
2) M(-2,2), N(4,-4)
Answer:
Problem 1) [tex] m = \dfrac{1}{4} [/tex] [tex] slope_{perpendicular} = -4 [/tex]
Problem 2) [tex] m = \dfrac{1}{3} [/tex] [tex] slope_{perpendicular} = -3 [/tex]
Step-by-step explanation:
[tex] slope = m = \dfrac{y_2 - y_1}{x_2 - x_1} [/tex]
[tex] slope_{perpendicular} = \dfrac{-1}{m} [/tex]
Problem 1) M(9,6), N(1,4)
[tex] slope = m = \dfrac{6 - 4}{9 - 1} = \dfrac{2}{8} = \dfrac{1}{4} [/tex]
[tex] slope_{perpendicular} = \dfrac{-1}{\frac{1}{4}} = -4 [/tex]
Problem 2) M(-2,2), N(4,-4)
[tex] slope = m = \dfrac{4 - 2}{4 - (-2)} = \dfrac{2}{6} = \dfrac{1}{3} [/tex]
[tex] slope_{perpendicular} = \dfrac{-1}{\frac{1}{3}} = -3 [/tex]
It is known that 80% of all brand A external hard drives work in a satisfactory manner throughout the warranty period (are "successes"). Suppose that n= 15 drives are randomly selected. Let X = the number of successes in the sample. The statistic X/n is the sample proportion (fraction) of successes. Obtain the sampling distribution of this statistic.
Answer:
P (x= 5) = 0.0001
P(x=3) = 0.008699
Step-by-step explanation:
This is a binomial distribution .
Here p = 0.8 q= 1-p = 1-0.8 = 0.2
n= 15
So we find the probability for x taking different values from 0 - 15.
The formula used will be
n Cx p^x q^n-x
Suppose we want to find the value of x= 5
P (x= 5) = 15C5*(0.2)^10*(0.8)^5 = 0.0001
P(x=3) = 15C3*(0.2)^12*(0.8)^3 = 9.54 e ^-7= 0.008699
Similarly we can find the values for all the trials from 0 -15 by substituting the values of x =0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15.
The value for p(x = 5) is 0.0001 and the value for p(x = 3) is 0.008699.
It is given that the 80% of all brand A external hard drives work in a satisfactory manner throughout the warranty period.
It is required to find the sampling distribution if n =15 samples.
What is sampling distribution?It is defined as the probability distribution for the definite sample size the sample is the random data.
We have p =80% = 0.8 and q = 1 - p ⇒ 1 -0.8 ⇒ 0.2
n = 15
We can find the probability for the given x by taking different values from 0 to 15
the formula can be used:
[tex]\rm _{n}^{}\textrm{C}_x p^xq^{n-x}[/tex]
If we find the value for p(x = 5)
[tex]\rm _{15}^{}\textrm{C}_5 p^5q^{15-5}\\\\\rm _{15}^{}\textrm{C}_5 0.8^50.2^{10}[/tex]⇒ 0.0001
If we find the value for p(x = 3)
[tex]\rm _{15}^{}\textrm{C}_3 0.8^30.2^{12}\\[/tex] ⇒
Similarly, we can find the values for all the trials from 0 to 15 by putting the values of x = 0 to 15.
Thus, the value for p(x = 5) is 0.0001 and the value for p(x = 3) is 0.008699.
Learn more about the sampling distribution here:
https://brainly.com/question/10554762
Help me please thank y’all
x= 30 degrees
Step-by-step explanation:
there's 180 degrees in a triangle. You can see 60 degrees right there. Theres a 90 degree angle right next to it. 180-150=30
Dan weighs 205 pounds but is only 5 feet 8 inches tall. Evan is 6 feet tall. How much would you expect Evan to weigh if they have the same height/weight ratio? WILL MARK BRAINLIST
Answer:
217.0588235294118
Step-by-step explanation:
Convert all height to inches.
5' 8" = 68 inches
6' = 72
205/68 = 3.014705882352941
Height/Weight Ratio * Evan's Height = 217.0588235294118
E
Homework: Practice
Exam 3
Question 7
Find the standard deviation for the group of data items.
14, 15, 16, 16, 17, 18
The standard deviation is
(Simplify your answer. Round to two decimal places as needed.)
9
Answer:
Step-by-step explanation:
Gabrielle's age is two times Mikhail's age. The sum of their ages is 30 . What is Mikhail's age?
Step-by-step explanation:
G=2m
m+G=30
m +2m =30
3m=30
m=10
A sample of 81 observations is taken from a normal population with a standard deviation of 5. The sample mean is 40. Determine the 95% confidence interval for the population mean.
Answer:
38.911≤p≤41.089
Step-by-step explanation:
The formula for calculating confidence interval for a population mean us as shown below;
CI = xbar ± Z×S/√N where;
xbar is the sample mean = 40
Z is the z score at 95% confidence interval = 1.96
S is the standard deviation = 5
N is the sample size = 81
Substituting this parameters in the formula we have;
CI = 40±1.96×5/√81
CI = 40±(1.96×5/9)
CI = 40±(1.96×0.556)
CI = 40±1.089
CI = (40-1.089, 40+1.089)
CI = (38.911, 41.089)
The 95% confidence interval for the population mean is 38.911≤p≤41.089
Answer:
38.9 ≤ U ≤ 41.1
Step-by-step explanation:
Mean, m = 40; standard deviation, α = 5; Confidence limit, U = 95% or 0.95
N = 81
The standard error, α(m) = α/√(N) = 5/√81 =5/9
Using table: 0.95 = 0.0379
Z(0.95) = 2 - 0.0379 = 1.9621 or 1.96
Hence, confidence interval = { m - 1.96(α/√N) ≤ U ≤ m +1.96(α/√N)}
But, 1.96(α/√N) = 1.96 X 5/9 = 1.96 X 0.56 = 1.1
(40 - 1.1 ≤ U ≤ 40 + 1.1)
∴ the confidence interval = 38.9 ≤ U ≤ 41.1
The following data represents the age of 30 lottery winners.
22 26 27 27 31 34
36 42 43 44 48 49
52 53 55 56 57 60
65 65 66 67 69 72
75 77 78 78 79 87
Complete the frequency distribution for the data.
Age Frequency
20-29
30-39
40-49
50-59
60-69
70-79
80-89
Answer:
Step-by-step explanation:
This is an example of a frequency distribution for a class interval. In order to complete the frequency distribution, we will count the number of data occurring in each group, and write that number as the frequency for that group. This is done as shown below:
Age Frequency ages in class
20-29 4 22, 26, 27, 27
30-39 3 31, 34, 36
40-49 5 42, 43, 44, 48, 49
50-59 5 52, 53, 55, 56, 57
60-69 6 60, 56, 65, 66, 67, 69
70-79 6 72, 75, 77, 78, 78, 79
80-89 1 87
Total 30