Subtract 98/49 from 21/40, Solve 21/40

Subtract 98/49 from 21/40

1^st number: 21/40, 2^nd number: 2 0/49

21/40 - 98/49 is -59/40.

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

Next, find the equivalent fraction of both fractional numbers with denominator 1960
For the 1st fraction, since 40 × 49 = 1960,
21/40 = 21 × 49/40 × 49 = 1029/1960
Likewise, for the 2nd fraction, since 49 × 40 = 1960,
98/49 = 98 × 40/49 × 40 = 3920/1960
Subtract the two like fractions:
1029/1960 - 3920/1960 = 1029 - 3920/1960 = -2891/1960
After reducing the fraction, the answer is -59/40

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