Subtract 56/60 from 80/21, Solve 3 17/21

Subtract 56/60 from 80/21

1^st number: 3 17/21, 2^nd number: 56/60

80/21 - 56/60 is 302/105.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 60 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 21 × 20 = 420,
80/21 = 80 × 20/21 × 20 = 1600/420
Likewise, for the 2nd fraction, since 60 × 7 = 420,
56/60 = 56 × 7/60 × 7 = 392/420
Subtract the two like fractions:
1600/420 - 392/420 = 1600 - 392/420 = 1208/420
After reducing the fraction, the answer is 302/105
In mixed form: 292/105

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