Subtract 21/63 from 20/15, Solve 1 5/15

Subtract 21/63 from 20/15

1^st number: 1 5/15, 2^nd number: 21/63

20/15 - 21/63 is 1/1.

Find the least common denominator or LCM of the two denominators:
LCM of 15 and 63 is 315

Next, find the equivalent fraction of both fractional numbers with denominator 315
For the 1st fraction, since 15 × 21 = 315,
20/15 = 20 × 21/15 × 21 = 420/315
Likewise, for the 2nd fraction, since 63 × 5 = 315,
21/63 = 21 × 5/63 × 5 = 105/315
Subtract the two like fractions:
420/315 - 105/315 = 420 - 105/315 = 315/315
After reducing the fraction, the answer is 1/1

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