Subtract 16/21 from 80/42, Solve 1 38/42

Subtract 16/21 from 80/42

1^st number: 1 38/42, 2^nd number: 16/21

80/42 - 16/21 is 8/7.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 21 is 42

Next, find the equivalent fraction of both fractional numbers with denominator 42
For the 1st fraction, since 42 × 1 = 42,
80/42 = 80 × 1/42 × 1 = 80/42
Likewise, for the 2nd fraction, since 21 × 2 = 42,
16/21 = 16 × 2/21 × 2 = 32/42
Subtract the two like fractions:
80/42 - 32/42 = 80 - 32/42 = 48/42
After reducing the fraction, the answer is 8/7
In mixed form: 11/7

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