Subtract 28/20 from 72/63, Solve 1 9/63

Subtract 28/20 from 72/63

1^st number: 1 9/63, 2^nd number: 1 8/20

72/63 - 28/20 is -9/35.

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

Next, find the equivalent fraction of both fractional numbers with denominator 1260
For the 1st fraction, since 63 × 20 = 1260,
72/63 = 72 × 20/63 × 20 = 1440/1260
Likewise, for the 2nd fraction, since 20 × 63 = 1260,
28/20 = 28 × 63/20 × 63 = 1764/1260
Subtract the two like fractions:
1440/1260 - 1764/1260 = 1440 - 1764/1260 = -324/1260
After reducing the fraction, the answer is -9/35

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