Subtract 48/21 from 72/18, Solve 4 0/18

Subtract 48/21 from 72/18

1^st number: 4 0/18, 2^nd number: 2 6/21

72/18 - 48/21 is 12/7.

Find the least common denominator or LCM of the two denominators:
LCM of 18 and 21 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 18 × 7 = 126,
72/18 = 72 × 7/18 × 7 = 504/126
Likewise, for the 2nd fraction, since 21 × 6 = 126,
48/21 = 48 × 6/21 × 6 = 288/126
Subtract the two like fractions:
504/126 - 288/126 = 504 - 288/126 = 216/126
After reducing the fraction, the answer is 12/7
In mixed form: 15/7

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