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Help thanksssssssssssss

Help thanksssssssssssss-example-1

2 Answers

2 votes
First, translate the words you're given into math: 2x-y = 60% of 5y.
60% = 60/100 = 0.60.
0.60(5y) = 3y

2x-y = 3y

>> If this is the SAT and you have to do percentage by hand, you can always use fractions. So, 60% = 60/100 = 6/10 = 3/5.
(3)/(5) * 5 = 3.
Another quick percentage trick is that 10% of anything is just that number with the decimal point moved to the left one space. For ex: 10% of 5 = 0.5. And then you can multiply 0.5 by 6 (because 10%*6 = 60%) to get 3.

Back to the problem:
Now you have 2x-y = 3y. You are looking for what
(y)/(x) equals to. Start by separating the x and y variables by putting them on opposite sides of the equal sign:
2x-y = 3y
2x = 4y

You want x and y on one side and numbers on the other side. You also want y to be on the top of the fraction. What you want to do is divide both sides by x first:

2x = 4y\\ 2 = 4 (y)/(x)

Finally, isolate the variables by dividing by 4 on both sides:

2 = 4 (y)/(x) \\ (y)/(x) = (2)/(4) \\ (y)/(x) = (1)/(2)

The answer is C) 1/2
User Kahonmlg
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5.6k points
4 votes
This question is read from left to right.
2x - y = 60% of 5y of means multiply.
2x - y = 60/100 * 5y = 300y /100 = 3y
2x - y = 3y Add y to both sides.
2x = 4y Divide by 2
x = 2y
Now divide by x which is a bit unusual.
1 = 2y/x Now divide by 2
1/2 = y/x

C <<<< answer

User Ramazan Binarbasi
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5.5k points