Subtract 40/49 from 21/72
21/72 - 40/49 is -617/1176.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 49 is 3528
Next, find the equivalent fraction of both fractional numbers with denominator 3528 - For the 1st fraction, since 72 × 49 = 3528,
21/72 = 21 × 49/72 × 49 = 1029/3528 - Likewise, for the 2nd fraction, since 49 × 72 = 3528,
40/49 = 40 × 72/49 × 72 = 2880/3528 - Subtract the two like fractions:
1029/3528 - 2880/3528 = 1029 - 2880/3528 = -1851/3528 - After reducing the fraction, the answer is -617/1176
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