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Solve the following proportion for the variable x

Solve the following proportion for the variable x-example-1

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Answer:

Explanation:

A proportion is a fancy way of saying that two fractions are the same. To find out what the missing number is, we can do some magic called cross-multiplication, which means we multiply the numbers that are diagonal from each other and make them equal. For example, if we have a proportion like a/b = c/d, we can cross-multiply and get ad = bc. Then we can find the missing number by moving things around until it's by itself. Let's try this trick on this problem:

7/x+2 = 4/x+1

Cross-multiply:

7(x+1) = 4(x+2)

Spread out:

7x + 7 = 4x + 8

Take away 4x from both sides:

3x + 7 = 8

Take away 7 from both sides:

3x = 1

Cut both sides by 3:

x = 1/3

So, the answer is x = 1/3.

User Arnaud Boeglin
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