Subtract 80/63 from 28/40, Solve 28/40

Subtract 80/63 from 28/40

1^st number: 28/40, 2^nd number: 1 17/63

28/40 - 80/63 is -359/630.

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

Next, find the equivalent fraction of both fractional numbers with denominator 2520
For the 1st fraction, since 40 × 63 = 2520,
28/40 = 28 × 63/40 × 63 = 1764/2520
Likewise, for the 2nd fraction, since 63 × 40 = 2520,
80/63 = 80 × 40/63 × 40 = 3200/2520
Subtract the two like fractions:
1764/2520 - 3200/2520 = 1764 - 3200/2520 = -1436/2520
After reducing the fraction, the answer is -359/630

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