Find two numbers a and b whose sum a+b is -3 and whose difference a−b is -5
Answer:
A=-4, b=1
Step-by-step explanation:
add those two function together u will got:
a+b+(a-b)=-3+(-5)
2a=-8
A=-4
-4+b=-3
B=1
The ages of undergraduate students in a state in a particular year approximately follows a normal distribution, with a mean
age of 20.6 years and a standard deviation of 1.3 years.
If the total number of undergraduate students in the state is 430,000, how many students are aged 19 years or more?
A)
123,000
B)
223,000
C)
313,000
D)
383,000
Bella invested $8,400 in an account paying an interest rate of 1.9% compounded continuously. Assuming no deposits or withdrawals are made, how long would it take, to the nearest tenth of a year, for the value of the account to reach $9890?
Answer:
8.6 years
Step-by-step explanation:
In one month, a farm produces 1200 pounds of potatoes. In the following month,
the amount of potatoes it produces increases by 15% over the previous month.
How many potatoes does it produce in the second month?
O 1280 pounds
O 1320 pounds
O 1350 pounds
O 1380 pounds
O 1450 pounds
1200=100%
=115%?
1200×115%\100%
=1380
How much is 54 + 12 = ?
Answer:
66
Step-by-step explanation:
please help !! i’ll give 5 stars if help.
Answer:
true
Step-by-step explanation:
there are two x-intercepts
Another name for a hexahedron is O A. cube O B. cylinder O C. pyramid O D. equilateral triangle
Solve for d.
–821 = d + –701
Answer:
d = -120
Step-by-step explanation:
-821 + 701 = d
d = -120
Please help!! Timed assignment
Arrange the figures in increasing order of their volumes. Use Pi =22/7
Answer:
see the list below
Step-by-step explanation:
did all the formulas for each and I believe the order is from (smallest to biggest)
1. The half sphere or hemisphere (3rd in the pic)
2.The pyramid
3.slanted cone
4.cone
5.slanted cylinder
6.and finally the cylinder
Volume of cylinder II< Volume of cylinder I< Volume of Cone II< Volume of pyramid <Volume of Cone I
What is volume?The amount of space occupied by a three-dimensional figure as measured in cubic units.
Volume of Cone I = 1/3 πr²h= 1/3*22/7*5*5*7
=25 cm³
Volume of cylinder I= πr²h= 22/7*4*4*5
= 251.42 cm³
Volume of hemisphere= 2/3*πr³= 2/3*22/7*3.5*3.5*3.5
= 89.833 cm³
Volume of pyramid = l*w*h= 10*5*6
= 100 cm³
Volume of cylinder II= πr²h= 22/7*6*6*8
= 905.14 cm³
Volume of Cone II= 1/3 πr²h= 1/3*22/7*4.5*4.5*7.5
=159.107 cm³
Learn more about volume here:
brainly.com/question/16134180
#SPJ2
Simplify −6+13x−7−16x
Formula to find commission
A commission is a percentage of total sales,
multiply the rate of commission by the total sales
PLEASE HELPPP 7TH GRADE MATHHHH!! WILL GIVE BRAINLIEST!! NEED RN PLEASE
Driving down the highway in separate vehicles, two friends realized that there were mile markers along each side of the road. They counted ten green markers for every mile they traveled. They also counted 8 yellow markers for each green marker. They text to each other their observations and wondered who was driving faster. Dev said he saw 110 green markers in 20 minutes. Mike said she saw 88 yellow markers in 2 minutes. Based on their observations, who is traveling faster?
Answer:
mike because he saw more markers in a less time than dev did
For one month, 500 elementary students kept a daily record of the hours they spent watching television. The average number of hours per week spent watching television was 28. The researchers conducting the study also obtained report cards for each of the students. They found that the students who did well in school tended to spend less time watching television than those students who did poorly. Listed are several possible statements concerning the results of this research. Place a check by every statement that you agree with based on this study.
a. The sample of 500 is too small to permit drawing conclusions about elementary students in general.
b. If a student decreased the amount of time spent watching television, his or her performance in school would improve.
c. Even though students who did well in school watched less television, this doesn't necessarily mean that watching television hurts school performance.
d. One month is not a long enough period of time to estimate how many hours the students really spend watching television.
e. I don't agree with any of these statements.
Answer:
a. The sample of 500 is too small to permit drawing conclusions about elementary students in general.
C. Even though students who did well in school watched less television, this doesn't necessarily mean that watching television hurts school performance.
Step-by-step explanation:
To make inferences about a general population from sample data, we must ensure that the data is considerably large enough and randomized, this is in other to ensure that the sample is representative of the population. Hence, Making conclusion about a very large population such as here, where we want to correlate performance and playing time, a very large sample which should be atleast 10% of the population should be employed. Hence, a sample of 500 ; for making Decison about general elementary students which should run into millions require more samples.
Also Recall that, correlation does not imply causation, The fact that there is a perceives relationship between grade or performance and time spent watching TV does not necessarily mean that poor grade was caused by long duration of hours spent watching television. Other, factors such as, level of intelligence, variation of teachers competence and so on may also be causal factors.
High value points! Please find the VALUE of x and y (my last problem for my work) please help!
Answer:
x=35
y=100
Step-by-step explanation:
x+15=50
x= 50-15
x= 35
y+30+50=180
y+80=180
y=180-80
y= 100
How do I deposit more money into my bank account
When you deposit cash at a bank or credit union, you typically need to use a deposit slip. That's simply a slip of paper that tells the teller where to put the money. Write your name and account number on the deposit slip (deposit slips are usually available at the lobby or drive-throug).
The Sine Function
According to the National Weather Service, the average monthly high temperature in the Dallas/Fort Worth, Texas area from the years of 2006-2008 is given by the following table:
Plot the data on a scatter plot., Produce a sine regression model for the data. Round the values for a, b, c, and d to the nearest 0.0001.
a. y = 67.577 sin(0.500 x - 1.959) + 20.077
b. y = 20.077 sin(0.500 x - 1.959) + 67.577
c. y = 20.077 sin (1.959 x - 0.500) + 67.577
d. y = 20.077 sin (67.577 x -1.959) + 0.500
Please select the best answer from the choices provided
Answer:
B. y = 20.077 sin(0.500 x - 1.959) + 67.577
Step-by-step explanation:
I calculated logically
Shreman drew a shape with these properties: •Four sides •Four right angles •Two sides have different lengths
Answer: the shape is a rectangle
Step-by-step explanation:
Answer:
Rectangle :)
Step-by-step explanation:
Ryan bought a new phone case that was originally $80, it is now on sale for $60. What was the percentage change?
Answer: 25% decrease
Step-by-step explanation:
80 - 60
----------- = 20/80 = 1/4 OR 25%
80
Hope this helped :)
8).
9).
7). Degrees
Degrees
Degrees
A
77
Teacrerit20
HELP ASAP PLEASE
Answer:
1) 47 degrees
2) 28 degrees
3) 26 degrees
Step-by-step explanation:
a triangle always equals 180 degrees, you add together the numbers you have then subtract it from 180 then you'll get your answer <3
PLEASE HELP
log (5x – 10) = log (6 – 5x)
Answer: look at the picture
Step-by-step explanation: Hope this help :D, Can I have a Brainliest I really needed it please
Please Help Me!
*Question Is Below Here*
Answer:
21
Step-by-step explanation:
2^3=8
7x6=42
42x8=336
336/ (10.6+5.4)
336/ 16= 21
Answer 21
A data set of 27 different numbers has a mean of 33 and a median of 33. A new data set is
created by adding 7 to each number in the original data set that is greater than the median and
subtracting 7 from each number in the original data set that is less than the median. Which of
the following measures does NOT have the same value in both the original and new data sets?
A.Median
B.Mean
C. Sum of the numbers
D. Standard deviation
Answer:
Option D.
Step-by-step explanation:
Suppose that we have a set of N values:
{x₁, x₂, ..., xₙ}
The median is the value in the middle, and the mean is calculated as:
[tex]M = \frac{(x_1 + x_2 + x_3 ... + x_n)}{N}[/tex]
Because here we have "the median" then we will assume that N is odd, and there is only one median, the value "k" (if N was even, the median would be the mean of the two middle values, that case is really similar to the case where N is odd, so solving only one of the cases is enough)
Now we add 7 to all the values greater than the median
We subtract 7 to all values smaller than the median.
Then the median remains unchanged (because we did not add nor subtract anything to the median).
The new mean will be:
[tex]M' = \frac{(x_1 - 7) + (x_2 - 7) + ... + (x_{k}) + ... + (x_n + 7)}{N} = \frac{(x_1 + x_2 + ... + x_n) + (-7)*(n/2 - 0.5) + 7*(n/2 - 0.5)}{N} = \frac{(x_1 + x_2 + ... + x_n)}{N} = M[/tex]
So the mean does not change.
Because the mean is computed as the sum of the numbers divided by N, and the mean does not change, and N does not change, then the sum of the numbers does not change.
Finally, the standard deviation is computed as:
[tex]SD = \sqrt{\frac{(x_1 - M)^2 + ... + (xn - M)^2}{N} }[/tex]
Because M does not change, if we add or subtract numbers to some of the values, the standard deviation will change (Because all the terms are squared, so the added and subtracted sevens don't cancel like in the previous cases)
Then the only value that does not have the same value in both the original and new data sets is the standard deviation.
plzzzzzzzz help for a brainly
Answer:
50
Step-by-step explanation:
50+40=90 and that's what you need
Answer:
50
Step-by-step explanation:
it's a right triangle so it has to equal 90 and since there is a 40 you will need 50 to equal 90
part 1. Use side ratios to determine if the triangles in each pair of similar. If so complete the similarity statement. NO LINKS!!!
9514 1404 393
Answer:
4) ΔEFG ~ ΔECD
6) Not Similar
Step-by-step explanation:
4) Shortest to longest sides are ...
EF : FG : GE = 14 : 16 : 20 = 7 : 8 : 10 (reduced)
EC : CD : DE = 7 : 8 : 10
The triangles have the same side length ratios, so are similar.
ΔEFT ~ ΔECD
__
6) Shortest to longest, the given sides have ratios ...
UT : TV = 71 : 84 (reduced)
GT : TH = 60 : 72 = 5 : 6 (reduced)
The side ratios are different, so the triangles are NOT SIMILAR.
Answer:
part 1. Use side ratios to determine if the triangles in each pair of similar. If so complete the similarity statement. NO LINKS!!!
The average amount of ozone in several cities across Pennsylvania was found in a study to correlate with the average number of asthma cases in those cities. What type of study was this
Answer:
Ecological study
Step-by-step explanation:
When the basis for the conclusion of a study is done an a group or population level rather than on a person, single or individual basis, then we refer to this as an ecological study. In the scenario described above, relationship between ozone in Pennsylvania and the number of asthma cases was generalized and presented on the mean or average level rather than being compared in terms of individual figure. Hence, research studies of this type or nature are classed as ecological study.
find the surface area of each figure (spheres and hemispheres)
Answer:
7. 1520.53 cm²
8. 232.35 ft²
9. 706.86 m²
10. 4,156.32 mm²
11. 780.46 m²
12. 1,847.25 mi²
Step-by-step explanation:
Recall:
Surface area of sphere = 4πr²
Surface area of hemisphere = 2πr² + πr²
7. r = 11 cm
Plug in the value into the appropriate formula
Surface area of the sphere = 4*π*11² = 1520.53 cm² (nearest tenth)
8. r = ½(8.6) = 4.3 ft
Plug in the value into the appropriate formula
Surface area of the sphere = 4*π*4.3² = 232.35 ft² (nearest tenth)
9. r = ½(15) = 7.5 m
Surface area of the sphere = 4*π*7.5² = 706.86 m² (nearest tenth)
10. r = ½(42) = 21 mm
Plug in the value into the formula
Surface area of hemisphere = 2*π*21² + π*21² = 2,770.88 + 1,385.44
= 4,156.32 mm²
11. r = 9.1 m
Plug in the value into the formula
Surface area of hemisphere = 2*π*9.1² + π*9.1² = 520.31 + 260.15
= 780.46 m²
12. r = 14 mi
Plug in the value into the formula
Surface area of hemisphere = 2*π*14² + π*14² = 1,231.50 + 615.75
= 1,847.25 mi²
A study finds that 80% of the local high school students text while doing homework. Ten students are selected at random from the local high
school. Which expression would be part of the process used to determine the probability that, at most, 7 of the 10 students text while doing homework?
Answer:
Step-by-step explanation:
Traffic cameras showed that 15 of every 50 cars passing through a certain intersection did
not fully stop at the stop sign. Based on this sample, what is the probability that a car
arriving at this intersection will not fully stop?
0 0.03
0 0.15
0.30
0 0.50
Answer:
C, 0.30
Step-by-step explanation:
First, simplify.
[tex]\frac{15}{50}[/tex] = [tex]\frac{3}{10}[/tex]
Next, divide
3 ÷ 10 = 0.30 or 0.3
Have a great day!
Answer:
0.30 is the probability that a car arriving at this intersection will not fully stop.Step-by-step explanation:
Given that:
Total number of cars passing = 50 cars Number of cars not fully stop at the stop sign = 15 carsTo Find:
What is the probability that a car arriving at this intersection will not fully stop?We know that:
P(E) = F/TWhere,
P(E) = Probability of an event F = Favorable outcomes = 15T = Total outcomes = 50Finding the probability that a car arriving at this intersection will not fully stop:
⟶ P(E) = 15/50
Multiply by 2 with both numerator and denominator.
⟶ P(E) = (15 × 2)/(50 × 2)
⟶ P(E) = 30/100
⟶ P(E) = 0.30
Hence,
The probability that a car arriving at this intersection will not fully stop is 0.30.Plz help this is due today NO LINKS OR GROSS PICTURES OR I Will REPORT And please show work
Answer:
the volume is 120
Step-by-step explanation:
the formula for volume with length times width times height. Just multiply 3 x 5 x 8
Which list shows all the factors of 36?
1, 2, 3, 4, 6, 9, 12, 18, 36
1, 2, 3, 4, 8, 9, 12, 18, 36
2,3, 4, 6, 9, 12, 18
2, 4, 6, 8, 9, 12, 18
Answer:
Step-by-step explanation:
1,2,3,4,6,9,12,18,36