Subtract 28/40 from 70/49, Solve 1 21/49

Subtract 28/40 from 70/49

1^st number: 1 21/49, 2^nd number: 28/40

70/49 - 28/40 is 51/70.

Find the least common denominator or LCM of the two denominators:
LCM of 49 and 40 is 1960

Next, find the equivalent fraction of both fractional numbers with denominator 1960
For the 1st fraction, since 49 × 40 = 1960,
70/49 = 70 × 40/49 × 40 = 2800/1960
Likewise, for the 2nd fraction, since 40 × 49 = 1960,
28/40 = 28 × 49/40 × 49 = 1372/1960
Subtract the two like fractions:
2800/1960 - 1372/1960 = 2800 - 1372/1960 = 1428/1960
After reducing the fraction, the answer is 51/70

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