Problem 1
Answer: 32
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Work Shown:
8/9 = x/36
36*8 = 9x
288 = 9x
9x = 288
x = 288/9
x = 32
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Problem 2
Answer: 6
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Work Shown:
15:18 = 5:x
15/18 = 5/x
15x = 18*5
15x = 90
x = 90/15
x = 6
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Problem 3
Answer: 3
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Work Shown:
x to 7 = 9 to 21
x/7 = 9/21
21x = 7*9
21x = 63
x = 63/21
x = 3