Subtract 28/40 from 42/49
42/49 - 28/40 is 11/70.
Steps for subtracting fractions
- 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,
42/49 = 42 × 40/49 × 40 = 1680/1960 - Likewise, for the 2nd fraction, since 40 × 49 = 1960,
28/40 = 28 × 49/40 × 49 = 1372/1960 - Subtract the two like fractions:
1680/1960 - 1372/1960 = 1680 - 1372/1960 = 308/1960 - After reducing the fraction, the answer is 11/70
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