Subtract 15/42 from 42/72, Solve 42/72

Subtract 15/42 from 42/72

42/72 - 15/42 is 19/84.

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,
42/72 = 42 × 7/72 × 7 = 294/504
Likewise, for the 2nd fraction, since 42 × 12 = 504,
15/42 = 15 × 12/42 × 12 = 180/504
Subtract the two like fractions:
294/504 - 180/504 = 294 - 180/504 = 114/504
After reducing the fraction, the answer is 19/84

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