Subtract 3/72 from 30/42, Solve 30/42

Subtract 3/72 from 30/42

30/42 - 3/72 is 113/168.

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

Next, find the equivalent fraction of both fractional numbers with denominator 504
For the 1st fraction, since 42 × 12 = 504,
30/42 = 30 × 12/42 × 12 = 360/504
Likewise, for the 2nd fraction, since 72 × 7 = 504,
3/72 = 3 × 7/72 × 7 = 21/504
Subtract the two like fractions:
360/504 - 21/504 = 360 - 21/504 = 339/504
After reducing the fraction, the answer is 113/168

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