Subtract 8/84 from 40/21, Solve 1 19/21

Subtract 8/84 from 40/21

1^st number: 1 19/21, 2^nd number: 8/84

40/21 - 8/84 is 38/21.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 84 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 21 × 4 = 84,
40/21 = 40 × 4/21 × 4 = 160/84
Likewise, for the 2nd fraction, since 84 × 1 = 84,
8/84 = 8 × 1/84 × 1 = 8/84
Subtract the two like fractions:
160/84 - 8/84 = 160 - 8/84 = 152/84
After reducing the fraction, the answer is 38/21
In mixed form: 117/21

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