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41 votes
41 votes
Matt and Sarah both have this problem on their math test

"Determine if the two fractions are proportional: 4/5 and 8/10"

Matt thinks the two fractions are not proportional, but Sarah disagrees and thinks they are proportional.

User Smooth
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1 Answer

15 votes
15 votes

Answer:

Sarah is right.

4/5 = 8/10

Explanation:

A proportion is when you set up two ratios (they look like fractions) equal to each other.

4/5 ?=? 8/10

CROSSMULTIPLY.

4×10 ?=? 5×8

40 = 40

They are equal to each other. You could kind of tell by inspection. Like if you times the 4/5 × 2/2 you get 8/10.

Another way to check on a calculator is to divide. 4÷5 equals 0.8 ALSO, 8÷10 same, also equals 0.8

User Leogps
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