Subtract 4/60 from 80/21, Solve 3 17/21

Subtract 4/60 from 80/21

1^st number: 3 17/21, 2^nd number: 4/60

80/21 - 4/60 is 131/35.

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,
4/60 = 4 × 7/60 × 7 = 28/420
Subtract the two like fractions:
1600/420 - 28/420 = 1600 - 28/420 = 1572/420
After reducing the fraction, the answer is 131/35
In mixed form: 326/35

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