Subtract 15/35 from 63/42, Solve 1 21/42

Subtract 15/35 from 63/42

1^st number: 1 21/42, 2^nd number: 15/35

63/42 - 15/35 is 15/14.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 35 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 42 × 5 = 210,
63/42 = 63 × 5/42 × 5 = 315/210
Likewise, for the 2nd fraction, since 35 × 6 = 210,
15/35 = 15 × 6/35 × 6 = 90/210
Subtract the two like fractions:
315/210 - 90/210 = 315 - 90/210 = 225/210
After reducing the fraction, the answer is 15/14
In mixed form: 11/14

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