Subtract 15/72 from 21/4, Solve 5 1/4

Subtract 15/72 from 21/4

1^st number: 5 1/4, 2^nd number: 15/72

21/4 - 15/72 is 121/24.

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,
21/4 = 21 × 18/4 × 18 = 378/72
Likewise, for the 2nd fraction, since 72 × 1 = 72,
15/72 = 15 × 1/72 × 1 = 15/72
Subtract the two like fractions:
378/72 - 15/72 = 378 - 15/72 = 363/72
After reducing the fraction, the answer is 121/24
In mixed form: 51/24

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