Subtract 20/40 from 21/98
21/98 - 20/40 is -2/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 98 and 40 is 1960
Next, find the equivalent fraction of both fractional numbers with denominator 1960 - For the 1st fraction, since 98 × 20 = 1960,
21/98 = 21 × 20/98 × 20 = 420/1960 - Likewise, for the 2nd fraction, since 40 × 49 = 1960,
20/40 = 20 × 49/40 × 49 = 980/1960 - Subtract the two like fractions:
420/1960 - 980/1960 = 420 - 980/1960 = -560/1960 - After reducing the fraction, the answer is -2/7
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