Subtract 21/63 from 98/20, Solve 4 18/20

Subtract 21/63 from 98/20

1^st number: 4 18/20, 2^nd number: 21/63

98/20 - 21/63 is 137/30.

Find the least common denominator or LCM of the two denominators:
LCM of 20 and 63 is 1260

Next, find the equivalent fraction of both fractional numbers with denominator 1260
For the 1st fraction, since 20 × 63 = 1260,
98/20 = 98 × 63/20 × 63 = 6174/1260
Likewise, for the 2nd fraction, since 63 × 20 = 1260,
21/63 = 21 × 20/63 × 20 = 420/1260
Subtract the two like fractions:
6174/1260 - 420/1260 = 6174 - 420/1260 = 5754/1260
After reducing the fraction, the answer is 137/30
In mixed form: 417/30

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