The difference of twice a number and 7 is 20. Find the number.

Answers

Answer 1

Answer:

twice the difference gives 2(difference). 7 = 14  20 = 40

Step-by-step explanation:


Related Questions

Alexander Litvinenko was poisoned with 10 micrograms of the radioactive substance Polonium-210. Since radioactive decay follows a compounded continuously model, we can determine the amount of substance left in Alexander Litvinenko's body at any given time. If Polonium-210 has a decay rate of .502%, then determine the amount of Polonium-210 left in his body after 40 days. Provide 3 decimal places and units in your answer.

Answers

Compounded continuously model are evaluated using exponential functions

There are 8.177 bacteria left after 40 days

The given parameters are:

[tex]\mathbf{a = 10}[/tex] --- the initial number of bacteria

[tex]\mathbf{r = 0.502\%}[/tex] --- the decay rate

[tex]\mathbf{n = 40}[/tex] --- the number of days

The amount of bacteria left each day is calculated using:

[tex]\mathbf{T_n = a \times (1 - r)^n}[/tex]

So, we have:

[tex]\mathbf{T_{40} = 10 \times (1 - 0.502\%)^{40}}[/tex]

Express percentage as decimal

[tex]\mathbf{T_{40} = 10 \times (1 - 0.00502)^{40}}[/tex]

Simplify the expression in bracket

[tex]\mathbf{T_{40} = 10 \times 0.99498^{40}}[/tex]

Evaluate

[tex]\mathbf{T_{40} = 8.1766}[/tex]

Approximate

[tex]\mathbf{T_{40} = 8.177}[/tex]

Hence, there are 8.177 bacteria left after 40 days

Read more about compounded continuously model at:

https://brainly.com/question/73731


I need help with this math problem

Answers

Answer: The drill will reach -915 feet after 18 days.

what is 1/5 divided by 9?

Answers

Answer:

9/5

Step-by-step explanation:

Just divide the 9 by 1 so it'll be 9/5 hope it helps

The water level in a lake was monitored and was noted to have changed -2 1/3 inches in one year. The next year it was noted to have changed -1 5/6 inches. What was the total change in the water level over the two years?

Answers

Answer:

The total change in water level over the past 2 years is [tex]\displaystyle -4 \frac{1}{6}[/tex].

General Formulas and Concepts:

Pre-Algebra

Order of Operations: BPEMDAS

Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to Right

Fractions

Proper and Improper

Numbers

Least Common Multiple (LCM)

Step-by-step explanation:

Step 1: Define

Identify

Year 1 water change:  [tex]\displaystyle -2 \frac{1}{3}[/tex]

Year 2 water change:  [tex]\displaystyle -1 \frac{5}{6}[/tex]

Step 2: Find Total Water Change

[Set up] Add yearly water changes:                                                                [tex]\displaystyle -2 \frac{1}{3} + -1 \frac{5}{6}[/tex][Fractions] Convert to improper:                                                                     [tex]\displaystyle \frac{-7}{3} - \frac{11}{6}[/tex][Fraction] Rewrite [LCM]:                                                                                  [tex]\displaystyle \frac{-14}{6} - \frac{11}{6}[/tex][Order of Operations] Subtract:                                                                       [tex]\displaystyle \frac{-25}{6}[/tex][Fraction] Convert to proper:                                                                           [tex]\displaystyle -4 \frac{1}{6}[/tex]

Can some please help me I will mark u brilliant

Answers

Question 2: -4/3

Question 3: -7/20

3. Your bedroom is 14 feet by 10 feet and your sister's room is 12 feet by 10 feet. If you
are going to paint both rooms the same color and the paint covers 250 square feet per
gallon, how much paint will you need if you are going to paint the walls and ceilings?
Assume the ceiling is 8 ft high.

Answers

Step-by-step explanation:

we paint the walls and ceilings.

and we ignore any doors or windows (no information about them).

so, each room has then 5 rectangles : 4 walls and 1 ceiling.

when we say a room is 14 ft × 10 ft, this also means there are 2 sides of 14 ft and 2 sides of 10 ft.

and the area is 14×10 ft².

the area of the ceiling is the same as the area of the floor : 14×10 = 140 ft²

for the walls we have 2 rectangles of 14×8 = 112 ft², and 2 rectangles of 10×8 = 80 ft² (remember, the height of the room is 8 ft).

for the sister's room it is similar.

just a 12×10 = 120 ft² ceiling.

and 2 rectangles of 12×8 = 96 ft² and again 2 rectangles of 10×8 = 80 ft² as walls.

altogether we have then

140 + 112 + 112 + 80 + 80 + 120 + 96 + 96 + 80 + 80 ft²

that is in total

996 ft²

how many gallons of paint do we need for this ?

well, 1 gallon per 250 ft².

so, how often does 250 fit into 996 ?

996 / 250 = 3.984 gallons.

since we get the paint most likely only in quantities of gallons, we need 4 gallons for the paint job.

Find the slope of the line that passes through:
(6,7) and (4,2)

Answers

Answer:

5/2

Step-by-step explanation:

Slope = Change in y/Change in x

Slope = 2 - 7/4 - 6

Slope = -5/-2

Slope = 5/2

-Chetan K


The sum of two numbers is 15 and the difference is 4. Let the two numbers be x and y.
Write down a pair of simultaneous equations involving x and y. Solve the equations.

Answers

Answer:

x=9.5 and y=5.5

Step-by-step explanation:

x+y=15

x-y=4

add

2x=19

x=9.5

y=15-9.5

y=5.5

x=9.5 and y=5.5

At a sale this week, a desk is being sold for $285.60. This is 34% of the original price.
What is the original price?

Answers

well, let's say the original price is "x", which namely 100% of the price of the product, we also know that 285.60 is 34% of that.

[tex]\begin{array}{ccll} amount&\%\\ \cline{1-2} x&100\\ 285.60&34 \end{array}\implies \cfrac{x}{285.60}=\cfrac{100}{34}\implies \cfrac{x}{285.60}=\cfrac{50}{17} \\\\\\ 17x=14280\implies x = \cfrac{14280}{17}\implies x = 840[/tex]

simplify
21m^2−122m+112/9m^2−196

Answers

Answer:

3m-8/7m+14

Step-by-step explanation:

find measurement 1 and 4

Answers

Answer:

the info they gave us is to suppose that angle 6 is = 126°

step 1:

We know that angle 8 = angle 6 = 126°

Why? — when a circle (360°) is split by 2 lines that intersect, there will be 2 equal pairs of angles formed

step 2:

angle 2 = angle 8 = 126°

Why? — they’re alternate angles

step 3:

angle 4 = angle 2

Why? — when a circle (360°) is split by 2 lines that intersect, there will be 2 equal pairs of angles formed

step 4:

angle 1 = 180-126 (angle 4) = 54°

Why? — total angles in a straight line = 180°

Key Term:

Alternate angles:

Alternate angles are angles that occur on opposite sides of the transversal line and have the same size. Alternate angles are equal: We can often spot interior alternate angles by drawing a Z shape: There are two different types of alternate angles, alternate interior angles and alternate exterior angles.

The side of an equilateral triangle is 12. Its area is


Select one:
a. 72
b. 48
c. 144
d. 36 square root 3

Answers

A≈62.35

..................

1/2 x 12 x 12 x sin(60)
Answer is :
36 square root 3

If $2,940.00 is invested for 4 months at 3.8% simple interest:
What is the amount of interest earned?

Answers

Answer:

I = $372.40

Step-by-step explanation:

Given the principal amount of $2,940, which is invested for 4 months at 3.8% interest rate:

Use the following simple interest formula to solve for the interest earned:

I = P × r × t

where:

I = interest earned

P = principal amount invested = $2,940

r = interest rate = 3.8% or 0.380

t = time = 4/12 months = ⅓ or 0.3333

Substitute to given values into the simple interest formula:

I = P × r × t

I = $2,940 × 0.380 × 0.3333

I = $372.40

Therefore, the simple interest earned in 4 months is $372.40.

For the two numbers listed, find two factors of the first number such that their product is the first number and their sum is the second number -12,-1

Answers


-4 x 3 = -12
-4 + 3 = -1

5) Placido pulls a rope attached to a wagon through a pulley at a rate of q m/s. With dimension as in Figure 5:

(a) Find a formula for the speed of the wagon in terms of q and the variable x in the figure.

(b) Find the speed of the wagon when x=0.6 if q=0.5 m/s.

Answers

The formula for the speed of the wagon can be found by using Pythagoras theorem, and chain rule of differentiation.

[tex](a) \ \mathrm{The \ speed \ of \ the \ wagon} , \ \dfrac{dx}{dt} = q -\dfrac{x}{\sqrt{x^2+ 5.76}}[/tex]

(b) When x = 0.6 and q = 0.5 m/s, the speed of the wagon is approximately 0.243 m/s.

Reasons:

(a) The distance from the cart to the pulley, r is given by Pythagoras's

theorem as follows;

r = √((3 - 0.6)² + x²) = √(2.4² + x²)

The speed of the wagon = [tex]\mathbf{\dfrac{dx}{dt}}[/tex]

The speed of the rope, q = [tex]\mathbf{\dfrac{dr}{dt}}[/tex]

By chain rule, we have;

[tex]\dfrac{dr}{dt} = \mathbf{\dfrac{dr}{dx} + \dfrac{dx}{dt}}[/tex]

[tex]\dfrac{dr}{dx} = \dfrac{x}{\sqrt{x^2+ 5.76}}[/tex]

Therefore;

[tex]\dfrac{dr}{dt} = q =\dfrac{x}{\sqrt{x^2+ 5.76}}+ \dfrac{dx}{dt}[/tex]

[tex]\mathrm{The \ speed \ of \ the \ wagon} , \ \dfrac{dx}{dt} = \underline{ q -\dfrac{x}{\sqrt{x^2+ 5.76}}}[/tex]

(b) The speed of the wagon when x = 0.6 if q = 0.5 m/s is given as follows;

[tex]\dfrac{dx}{dt} = 0.5 -\dfrac{0.6}{\sqrt{0.6^2+ 5.76}} =\sqrt{\dfrac{1}{17} } \approx 0.243[/tex]

The speed of the wagon when x = 0.6 and q = 0.5 m/s, [tex]\dfrac{dx}{dt}[/tex] ≈ 0.243 m/s

Learn more here:

https://brainly.com/question/17081984

A hummingbird lives in a nest that is 12 meters high in a tree. The hummingbird flies 15
meters to get from its nest to a flower on the ground. How far is the flower from the base of
the tree?

Answers

Answer:

The flower is 9 meters from the base of the tree.

Step-by-step explanation:

Use the Pythagorean theorem to solve. We are given the length of one leg and the length of the hypotenuse of a right triangle.

[tex]a^{2} +b^{2} =c^{2}[/tex]

where a and b are the legs, and c is the hypotenuse.

Plug in the given values and solve:

[tex]x^{2} +12^{2} =15^{2} \\x^{2} +144=255\\x^{2} =81\\x=9[/tex]

The flower is 9 meters from the base of the tree.

What is the value of x?
14(6x−2)=x−2
A)-3
B)2
C)-7
D)-9

Answers

14(6x-2)=x-2

84x-28=x-2

84x-x= 28-2

83x = 26

x = 26/83

there are no corect answer below

ok done. Thank to me :>

18.which the venn diagram illutrates A-B?​

Answers

Answer:

Option B is correct answer

Simple Arcs and Sectors question attached. First person to answer correctly gets 50 points. Good Luck!!

Answers

Step-by-step explanation:

a=12/56°

b=14/65°

c=238°

4. In a simple random sample of 120 women and 150 men from
a population of 150,000, 25% of the women and 37% of the men
are smokers. Suppose you are interested in comparing the
proportion of smokers by sex, compute the Z statistic.

Answers

The z-test compares the two sample to determine the existence of a

difference in the two proportion.

The Z-statistic or test of the difference in proportion is approximately -2.106.

Reasons:

The given parameter are;

Number of women, n₁ = 120 women

Number of men, n₂ = 150 men

The population size = 150,000

Percentage of women that are smokers in population, [tex]\hat p_1[/tex] = 25%

Percentage of men that are smokers in population, [tex]\hat p_2[/tex] = 37%

The Z statistic is given as follows;

[tex]\displaystyle Z= \mathbf{\frac{\hat{p}_1-\hat{p}_2}{\sqrt{\hat{p}(1-\hat{p})\left (\frac{1}{n_{1}}+\frac{1}{n_{2}} \right )}}}[/tex]

Number of men = 0.37 × 150 = 55.5

Number of women = 0.25 × 120 = 30

[tex]\displaystyle \hat p = \frac{55.5 + 30}{150 + 120} = \frac{19}{60}[/tex]

Which gives;

[tex]\displaystyle Z=\frac{0.25-0.37}{\sqrt{\frac{19}{60} (1-\frac{19}{60} )\left (\frac{1}{120}+\frac{1}{150} \right )}} \approx -2.106[/tex]

The Z-statistic is approximately -2.106

Learn more here:

https://brainly.com/question/15936512

For any nonnegative real number a, (a)2 =
=
O A. a2
O B. va
Ос. а
O D. 1
SUBMIT

Answers

Answer:

C

Step-by-step explanation:

For example, if a is equal to 2.

[tex] \sqrt{2} {}^{2} = 2[/tex]

The answer is still the given number a.

The solution of the expression √a² is,

⇒ a

What is an expression?

Mathematical expression is defined as the collection of the numbers variables and functions by using operations like addition, subtraction, multiplication, and division.

Given that;

The expression is,

⇒ √a²

Where, 'a' is nonnegative real number.

Now, We can simplify as;

⇒ √a²

⇒ √ a × a

⇒ a

Thus,  The solution of the expression √a² is,

⇒ a

Learn more about the mathematical expression visit:

brainly.com/question/1859113

#SPJ5

$200 is shared between Bill and Ann. Ann’s share is $50 more than Bill’s share. Calculate the size of each of their shares.

Answers

First subtract the difference between the two:

200 - 50 = 150

Now divide that by 2:

150/2 = 75

Bills share is $75

Now add the $50 to 75 to get Ann's share:

75 + 50 = $125

Ann's share is $125

Bill's share is $75

calculate lim F(X)
[tex] {x }^{2} + 1 - 3 \frac{ ln(x) }{x} [/tex]

Answers

[tex]Hiya![/tex]

Sokka is here to help!!

Here's the step:

[tex]x^2+1-3\frac{In(x)}{x}[/tex]

[tex]Mutiply[/tex] [tex]by:[/tex] [tex]3[/tex]

[tex]. \frac{In(x)}{x} :\frac{3In(x)}{x}[/tex]

[tex]= x^2+1-\frac{3In(x)}{x}[/tex]

ANSWER:

[tex]= x^2+1-\frac{3In(x)}{x} .[/tex]

Hopefully, this helps you!!

[tex]Sokka[/tex]

What is the slope of any line that is perpendicular to the line that contains the points (8,8) and (12,12)

Answers

Answer: 1

Step-by-step explanation:

12-8=4

12-8=4

4 over 4 is 1

if it perpendicular then it's the opposite reciprocal

hope that help

Incredibly, Enzo wins 5 tickets from every game, and Beatriz wins 11 tickets from every game. When they stopped playing games, Enzo and Beatriz had won the same number of total tickets.
What is the minimum number of games that Enzo could have played?

Answers

Answer:

Enzo must have played 11 games.

Step-by-step explanation:

Since Enzo earns 5 tickets from every game and Beatriz wins 11 tickets from each game, we have to find the LCM (Least Common Multiple) since they earned the same amount of tickets when they stopped.

The LCM of 11 and 5 is 55.

To see how many games they both played we have to divide the amount of tickets they earn each time from the LCM (55).

Since Enzo earns 5 tickets from each game and both Enzo and Beatrice earned 55, Enzo must've played 11 games.

(If that makes sense lol)

Find the missing number.Write your answer on your answer sheet.
3/5÷2/6= 3/5÷6/2=

Answers

Answer :

[tex] \huge \bf \color{gold} \frac{3}{5} \div \frac{2}{6} = [/tex]

[tex] \tt \frac{3}{5} \times \frac{6}{2} = [/tex]

[tex] \tt \frac{18 \div 2}{10 \div 2} = [/tex]

[tex] \tt \frac{9}{5} = [/tex]

[tex] \boxed {\color{blue}{ 1 \frac{4}{5}}}[/tex]

THE RESULT IS 1 4/5

Answer:

The solution is 9/5 and 1/5

Step-by-step explanation:

3/5÷2/6

= 3/5×6/2

= 3/5×3

= 9/5

3/5÷6/2

= 3/5×2/6

= 3/5×1/3

= 1/5

what is 2x-3 when x=1

Answers

Answer:
-1


Explanation: when there is a number with a letter next to it with nothing between then you multiply that number times the letter then minus what you got from that buy the other number

Find the angle measures. Justify your responses.
m
a
21
34
b
65
7/8
Given: a 1b, m_2=3x +20°,
m27=2x -10°
Find: m3, m26
mZ3 =
=
m26=
=

Answers

Answer:

m∠3 = 2x - 10° and m∠6 = 3x + 20

m∠3 = 58°          ;    m ∠6 = 122°

Step-by-step explanation:

a ║ b

m∠2 = m∠6                     If ║ cut by a transversal, then corresponding angles

                                         are ≅ and =

m∠7 = m∠3                   If ║ cut by a transversal, then corresponding angles

                                       are ≅ and =

m∠2 = 3x + 20              Given

m∠7 = 2x - 10                 Given    

m∠6 + m∠3 = 180°         If ║ cut by a transversal, then each pair of same-side

                                       interior angles (also called consecutive interior angles

                                       are supplementary (sum = 180°) .    

3x + 20 + 2x - 10 = 180°

5x + 10 = 180°

5x = 170°

x = 34°

Answer:   m∠3 = 2x - 10° and m∠6 = 3x + 20

                m∠3 = 2(34) - 10  ;    m∠6 = 3(34) + 20

                 m∠3 = 58°          ;    m ∠6 = 122°

                                 


Which distance formula or formulas show(s) a joint variation?

Answers

Answer:

II and III only

Step-by-step explanation:

One variable quantity is said to vary jointly as a number of other variable quantities, when it varies directly as their product.

The annual number of burglaries in a town rose by 50% in 2012 and fell by 10% in 2013. hence the total number of burglaries increased by 40% over the two year period.
a. by what percent has the number of burglaries actually changed in the two-year period?
b. by what percent would the crime have to decrease in the second year in order for the change over the two-year period to actually be a 40% increase?

Answers

The percentage change in the number of burglaries over the two-year period is 35% .

The change in burglaries over the two-year period to have  a 40% increase is 6.7%.

Let's assume that the annual number of burglaries in 2011 is 1000. After the 50% increase in 2012, the number of burglaries would be: 1000(1.50) = 1500.

The number of burglaries after the 10% reduction in 2013 would be: 1500(.90) = 1350

The change in burglaries over the two-year period = (1350 / 100) - 1 = 35%

In order to determine how much burglaries would have to reduce in order to have a 40% change in burglaries, this formula would be used

(x - 1000) / 1000 = 0.40

x - 1000 = 400

x = 1400

The change in burglaries over the two-year period to have  a 40% increase = (1400 / 1500) - 1 = 6.7%

To learn more, please check: https://brainly.com/question/9350849

Other Questions
When salt water i added to a plant cell why does the cell membrane srink please someone help me answer this question. file is attached. What persuasive writing techniques does he use in the letter toentice other Anglo-Americans? How many cups are in 1 liter Complete the following to show how the expression can be simplified using the Commutative and Associative Properties of Multiplication.Enter the correct numbers in the boxes.(0.5)(7)(2)= ( )( )(2)=(7)[( )( )]=(7)( )= HIPAA is important because it can help reduce _____.medical discriminationthe incidence of diseasethe cost of health carepatient wait times How do you use "Speaker of the House" in a sentence for AP Government? Ill mark the brainiest Which type of transport is shownthis diagram?EndocytosisIon pumpExocytosisFacilitated DiffusionI need the Answer ASAP "Accounting and bookeeping are the same" Do you agree? Explain A good thesis statement coversA. Four or more topicsB. Two topicsC. Three topicsD. One topic Which theorem does it offer proof of? Select the correct expression. Which expression is equivalent to 5^4 (5^-2)^3 ?5-^35^25^-25^-1 if [tex]a_{1}[/tex]=4 and [tex]a_{n}[/tex]= [tex]5a_{n-1}[/tex]-1 then find the value of [tex]a_{3}[/tex] Check the given measurements whether it could make a triangle (a) 7 cm, 2 cm and 5 cm (b) 10 cm, 12 cm and 14 cm. The graph of f(x)=16^x is reflected about the x-axis and shifted upward 8 units. What is the equation of the new function, g(x) ? Find the dimension of the gravitational constant in this equation F=Gm1m2/rr The boy to ____________ I lend my money is poor. *A. whomB. whoseC. whoD. that Which country is the star marking on this map of Africa? Which Enlightenment idea encouraged colonists to exercise a new type of political system decided by citizens through a vote?