Subtract 21/56 from 72/18, Solve 4 0/18

Subtract 21/56 from 72/18

1^st number: 4 0/18, 2^nd number: 21/56

72/18 - 21/56 is 29/8.

Find the least common denominator or LCM of the two denominators:
LCM of 18 and 56 is 504

Next, find the equivalent fraction of both fractional numbers with denominator 504
For the 1st fraction, since 18 × 28 = 504,
72/18 = 72 × 28/18 × 28 = 2016/504
Likewise, for the 2nd fraction, since 56 × 9 = 504,
21/56 = 21 × 9/56 × 9 = 189/504
Subtract the two like fractions:
2016/504 - 189/504 = 2016 - 189/504 = 1827/504
After reducing the fraction, the answer is 29/8
In mixed form: 35/8

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