Subtract 30/7 from 72/15, Solve 4 12/15

Subtract 30/7 from 72/15

1^st number: 4 12/15, 2^nd number: 4 2/7

72/15 - 30/7 is 18/35.

Find the least common denominator or LCM of the two denominators:
LCM of 15 and 7 is 105

Next, find the equivalent fraction of both fractional numbers with denominator 105
For the 1st fraction, since 15 × 7 = 105,
72/15 = 72 × 7/15 × 7 = 504/105
Likewise, for the 2nd fraction, since 7 × 15 = 105,
30/7 = 30 × 15/7 × 15 = 450/105
Subtract the two like fractions:
504/105 - 450/105 = 504 - 450/105 = 54/105
After reducing the fraction, the answer is 18/35

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