Subtract 49/80 from 21/36
21/36 - 49/80 is -7/240.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 80 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 36 × 20 = 720,
21/36 = 21 × 20/36 × 20 = 420/720 - Likewise, for the 2nd fraction, since 80 × 9 = 720,
49/80 = 49 × 9/80 × 9 = 441/720 - Subtract the two like fractions:
420/720 - 441/720 = 420 - 441/720 = -21/720 - After reducing the fraction, the answer is -7/240
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