Subtract 21/49 from 4/40
4/40 - 21/49 is -23/70.
Steps for subtracting fractions
- 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,
4/40 = 4 × 49/40 × 49 = 196/1960 - Likewise, for the 2nd fraction, since 49 × 40 = 1960,
21/49 = 21 × 40/49 × 40 = 840/1960 - Subtract the two like fractions:
196/1960 - 840/1960 = 196 - 840/1960 = -644/1960 - After reducing the fraction, the answer is -23/70
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