Subtract 15/7 from 84/21, Solve 4 0/21

Subtract 15/7 from 84/21

1^st number: 4 0/21, 2^nd number: 2 1/7

84/21 - 15/7 is 13/7.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 7 is 21

Next, find the equivalent fraction of both fractional numbers with denominator 21
For the 1st fraction, since 21 × 1 = 21,
84/21 = 84 × 1/21 × 1 = 84/21
Likewise, for the 2nd fraction, since 7 × 3 = 21,
15/7 = 15 × 3/7 × 3 = 45/21
Subtract the two like fractions:
84/21 - 45/21 = 84 - 45/21 = 39/21
After reducing the fraction, the answer is 13/7
In mixed form: 16/7

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