Subtract 21/72 from 42/4, Solve 10 2/4

Subtract 21/72 from 42/4

1^st number: 10 2/4, 2^nd number: 21/72

42/4 - 21/72 is 245/24.

Find the least common denominator or LCM of the two denominators:
LCM of 4 and 72 is 72

Next, find the equivalent fraction of both fractional numbers with denominator 72
For the 1st fraction, since 4 × 18 = 72,
42/4 = 42 × 18/4 × 18 = 756/72
Likewise, for the 2nd fraction, since 72 × 1 = 72,
21/72 = 21 × 1/72 × 1 = 21/72
Subtract the two like fractions:
756/72 - 21/72 = 756 - 21/72 = 735/72
After reducing the fraction, the answer is 245/24
In mixed form: 105/24

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