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2 votes
Colin reduces a 15in by 21in photo to a 5in by 7in. What scale factor did he use?

2 Answers

5 votes

Answer: 3:1

Explanation:

We can model this problem using ratios, we start with a ratio of 15:21 and we know we went down to a 5:7. To make both equivalent we divide both 15 and 21 by 3, meaning the ratio between the two is 3:1.

User Scheintod
by
5.0k points
5 votes

Answer:

1/3

Explanation:

15/5=3

21/7=3

User Red Swan
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4.9k points