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3 years ago

Gwen has recently purchased a cottage. She has arranged

1 answer:

5 0

A) 0.8
B) 0.24
C) 0.56
D) 0.44

For A, since 1 in 5 is dry, 4 in 5 are not; 4/5 = 0.8

For B, we know that 30%, 0.3, of the ones that are not dry are contaminated:
0.3(0.8) = 0.24

For C, 100%-30%=70% of wells that are not dry are not contaminated; 0.7(0.8) = 0.56

For D, she will either have contaminated water or no water:
0.24+0.2 = 0.44

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Name two decimals whose sum is less then 1

harina [27]

0.1 0.2 because its only sum of only 0.3

5 0

3 years ago

student randomly receive 1 of 4 versions(A, B, C, D) of a math test. What is the probability that at least 3 of the 5 student te

alexdok [17]

Answer:

1.2%

Step-by-step explanation:

We are given that the students receive different versions of the math namely A, B, C and D.

So, the probability that a student receives version A = $\frac{1}{4}$ .

Thus, the probability that the student does not receive version A = $1-\frac{1}{4}$ = $\frac{3}{4}$ .

So, the possibilities that at-least 3 out of 5 students receive version A are,

1) 3 receives version A and 2 does not receive version A

2) 4 receives version A and 1 does not receive version A

3) All 5 students receive version A

Then the probability that at-least 3 out of 5 students receive version A is given by,

$\frac{1}{4}\times \frac{1}{4}\times \frac{1}{4}\times \frac{3}{4}\times \frac{3}{4}$ + $\frac{1}{4}\times \frac{1}{4}\times \frac{1}{4}\times \frac{1}{4}\times \frac{3}{4}$ + $\frac{1}{4}\times \frac{1}{4}\times \frac{1}{4}\times \frac{1}{4}\times \frac{1}{4}$

= $(\frac{1}{4})^3\times (\frac{3}{4})^2+(\frac{1}{4})^4\times (\frac{3}{4})+(\frac{1}{4})^5$

= $(\frac{1}{4})^3\times (\frac{3}{4})[\frac{3}{4}+\frac{1}{4}+(\frac{1}{4})^2]$

= $(\frac{3}{4^4})[1+\frac{1}{16}]$

= $(\frac{3}{256})[\frac{17}{16}]$

= 0.01171875 × 1.0625

= 0.01245

Thus, the probability that at least 3 out of 5 students receive version A is 0.0124

So, in percent the probability is 0.0124 × 100 = 1.24%

To the nearest tenth, the required probability is 1.2%.

4 0

3 years ago

eight more than the product of four and a number is equivalent to seven less than the same number in equation form.

Georgia [21]

4n + 8 = n - 7
(In which 'n' represents the unknown number)

(4n + 8): "Eight more than the product of four and a number"

(= n - 7): "Is equivalent to seven less than the same number in equation form."

Subtract 8 from both sides:
4n = n - 15

Subtract n from both sides:
3n = -15

Divide both sides by 3:
n = -5

5 0

3 years ago

Which of the following describes a rate?

malfutka [58]

Answer:

All of them

Step-by-step explanation:

8 0

3 years ago

Which expression has the same value as 37.4 - 54.9?

GrogVix [38]

Answer:

Step-by-step explanation:

In the original expression = 37.4 - 54.9 = -17.5

So, we have to solve all the equations but 1 of them has to equal to -17.5

A) -54.9 + (-37.4) = -92.3

Remove parentheses

= -54.9 - 37.4

Subtract the numbers

-92.3

B) 54.9 - 37.4 = 17.5

Since 54.9 is greater than 37.4 just subtract normally

4 14

5 4. 9 < ------- Line up the decimal points like this

- 3 7. 4 <--------- Subtract the decimals

-----------------

1 7 . 5 <---------- This is the final answer to B.

C) 37.4 - (- 54.9) = 92.3

Change the sign to addition

=37.4 + 54.9

Add the numbers normally

54.9

+ 37. 4

--------------

92.3

D) 37.4 + (-54.9) = -17.5

Change the sign to subtraction

= 37.4 - 54.9

Subtract them normally (but as you can see you are subtracting a smaller number from a larger number so heres a trick that you can use switch the equation by putting the larger number in first like this....)

54.9 - 37.4 = 17.5 (REMEMBER the answer is not 17.5 because the original equation of D is reversed 37.4 - 54.9 so in this case your answer should be

- 17.5)

37.4 - 54.9 = -17.5

Your final answer is D because it matches 37.4 - 54.9.

Hope this helps!

3 0

3 years ago

Read 2 more answers