Subtract 3/72 from 21/16, Solve 1 5/16

Subtract 3/72 from 21/16

1^st number: 1 5/16, 2^nd number: 3/72

21/16 - 3/72 is 61/48.

Find the least common denominator or LCM of the two denominators:
LCM of 16 and 72 is 144

Next, find the equivalent fraction of both fractional numbers with denominator 144
For the 1st fraction, since 16 × 9 = 144,
21/16 = 21 × 9/16 × 9 = 189/144
Likewise, for the 2nd fraction, since 72 × 2 = 144,
3/72 = 3 × 2/72 × 2 = 6/144
Subtract the two like fractions:
189/144 - 6/144 = 189 - 6/144 = 183/144
After reducing the fraction, the answer is 61/48
In mixed form: 113/48

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