Subtract 9/42 from 9/72, Solve 9/72

Subtract 9/42 from 9/72

9/72 - 9/42 is -5/56.

Find the least common denominator or LCM of the two denominators:
LCM of 72 and 42 is 504

Next, find the equivalent fraction of both fractional numbers with denominator 504
For the 1st fraction, since 72 × 7 = 504,
9/72 = 9 × 7/72 × 7 = 63/504
Likewise, for the 2nd fraction, since 42 × 12 = 504,
9/42 = 9 × 12/42 × 12 = 108/504
Subtract the two like fractions:
63/504 - 108/504 = 63 - 108/504 = -45/504
After reducing the fraction, the answer is -5/56

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