Subtract 30/72 from 21/49
21/49 - 30/72 is 1/84.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 49 and 72 is 3528
Next, find the equivalent fraction of both fractional numbers with denominator 3528 - For the 1st fraction, since 49 × 72 = 3528,
21/49 = 21 × 72/49 × 72 = 1512/3528 - Likewise, for the 2nd fraction, since 72 × 49 = 3528,
30/72 = 30 × 49/72 × 49 = 1470/3528 - Subtract the two like fractions:
1512/3528 - 1470/3528 = 1512 - 1470/3528 = 42/3528 - After reducing the fraction, the answer is 1/84
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