Subtract 72/18 from 21/4, Solve 5 1/4

Subtract 72/18 from 21/4

1^st number: 5 1/4, 2^nd number: 4 0/18

21/4 - 72/18 is 5/4.

Find the least common denominator or LCM of the two denominators:
LCM of 4 and 18 is 36

Next, find the equivalent fraction of both fractional numbers with denominator 36
For the 1st fraction, since 4 × 9 = 36,
21/4 = 21 × 9/4 × 9 = 189/36
Likewise, for the 2nd fraction, since 18 × 2 = 36,
72/18 = 72 × 2/18 × 2 = 144/36
Subtract the two like fractions:
189/36 - 144/36 = 189 - 144/36 = 45/36
After reducing the fraction, the answer is 5/4
In mixed form: 11/4

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