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3 years ago

You earned a 90% on a science test. You answered 18 questions correctly. How many questions were on the test?

Mathematics

2 answers:

Kruka [31]3 years ago

8 0

This is an easy one!

Answer = 20.

(18/20) x 100 = 90%

So, 20 questions!

zalisa [80]3 years ago

5 0

There were twenty questions on the test, we can figure this out by writing your word problem as an equation: x= the amount of questions there are on the test, with this in mind the equation will be written out 18/x=90%, then do the same to both sides of the equation, divide both sides by .90 which gets rid of the x on the left side and 18 divided by .90 = 20. So X = 20.

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Can i get help with math? (picture provided) grade 9 13-18

asambeis [7]

Answer:

I dont know what you are supposed to answer with but I'll try to help you out. I take it that you have to find the letter ex. the letter d in 1/2d = 7. What you have to do is to get the d by itself and in order to do that you must move the 1/2 over to the 7. So what you would have to do is take the fraction that has the letter on it and move it to the whole number side or the side without the letter but without moving the d. The d stays on one side while the other numbers are on the other side. When you move the 1/2 over it should look like this sort of due to the limitations of only being able to use text: d = 7 ÷ 1/2. Now after that you have to divide 7 by 1/2 or .5 for question 13 in this instance. Your answer for 13 should be this: d = 4.5 Make sure to show all your work just in case.

13. d = 4.5

14. 18 = f

15. -9 = s

16. -24 = r

17. 0.125 = y

18. -3 = v

Hope I could help as I am also a fellow 9th grader

6 0

4 years ago

Read 2 more answers

Meghan needs to board her cats and dogs at a kennel while she's on vacation. Pet Hotel charges $42.50 for a cat and $64.00 for a

Alex Ar [27]

Answer:

3 dogs and 2 cats.

Step-by-step explanation:

In this case we can solve it using a 2x2 system of equations, like this:

let x: number of cats

let y: number of dogs

So:

42.5 * x + 64 * y = 277

35.5 * x + 50.5 * y = 222.5 => x = (222.5 - 50.5 * y) /35.5

Replacing, we are left with that:

42.5 * (222.5 - 50.5 * y) /35.5 + 64 * y = 277

266.37- 60.45 * y + 64 * y = 277

64 * y - 60.45 * y = 277 - 266.37

3.55 * y = 10.63

y = 10.63 / 3.55

y = 2.99, about 3

Now to calculate x:

x = (222.5 - 50.5 * 3) /35.5

x = 2

Which means that it has a total of 3 dogs and 2 cats.

3 0

3 years ago

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Bank account A starts with $5,000 and grows by $1,000

grandymaker [24]

This should be right! $5,000 + $1,000x

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3 years ago

Simplify the expression below. (-5 × -4)÷(-3+5)

ohaa [14]

Answer:

-10

Step-by-step explanation:

7 0

3 years ago

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An example of consecutive odd integers is 23, 25, 27, and 29. Find four consecutive odd integers with a sum of 160. Show your wo

Andrew [12]

Step1: Define an odd integer.
Define the first odd integer as (2n + 1), for n = 0,1,2, ...,
Note that n is an integer that takes values 0,1,2, and so no.

Step 2: Create four consecutive odd integers.
Multiplying n by 2 guarantees that 2n will be zero or an even number.
Therefore (2n + 1) is guaranteed to be an odd number.
By adding 2 to the odd integer (2n+1), the next number (2n+3) will also be an odd integer.

Let the four consecutive odd integers be
2n+1, 2n +3, 2n +5, 2n +7

Step 3: require that the four consecutive integers sum to 160.
Because the sum of the four consecutive odd integers is 160, therefore
2n+1 + 2n+3 + 2n+5 + 2n +7 = 160
8n + 16 = 160
8n = 144
n = 18

Because 2n = 36, the four consecutive odd integers are 37, 39, 41, 43.

Answer: 37,39,41,43

8 0

3 years ago