Subtract 20/40 from 72/63, Solve 1 9/63

Subtract 20/40 from 72/63

1^st number: 1 9/63, 2^nd number: 20/40

72/63 - 20/40 is 9/14.

Find the least common denominator or LCM of the two denominators:
LCM of 63 and 40 is 2520

Next, find the equivalent fraction of both fractional numbers with denominator 2520
For the 1st fraction, since 63 × 40 = 2520,
72/63 = 72 × 40/63 × 40 = 2880/2520
Likewise, for the 2nd fraction, since 40 × 63 = 2520,
20/40 = 20 × 63/40 × 63 = 1260/2520
Subtract the two like fractions:
2880/2520 - 1260/2520 = 2880 - 1260/2520 = 1620/2520
After reducing the fraction, the answer is 9/14

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