Subtract 42/49 from 21/30
21/30 - 42/49 is -11/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 49 is 1470
Next, find the equivalent fraction of both fractional numbers with denominator 1470 - For the 1st fraction, since 30 × 49 = 1470,
21/30 = 21 × 49/30 × 49 = 1029/1470 - Likewise, for the 2nd fraction, since 49 × 30 = 1470,
42/49 = 42 × 30/49 × 30 = 1260/1470 - Subtract the two like fractions:
1029/1470 - 1260/1470 = 1029 - 1260/1470 = -231/1470 - After reducing the fraction, the answer is -11/70
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