Subtract 27/70 from 63/42, Solve 1 21/42

Subtract 27/70 from 63/42

1^st number: 1 21/42, 2^nd number: 27/70

63/42 - 27/70 is 39/35.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 70 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 70 × 3 = 210,
27/70 = 27 × 3/70 × 3 = 81/210
Subtract the two like fractions:
315/210 - 81/210 = 315 - 81/210 = 234/210
After reducing the fraction, the answer is 39/35
In mixed form: 14/35

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