Subtract 49/70 from 21/35
21/35 - 49/70 is -1/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 35 and 70 is 70
Next, find the equivalent fraction of both fractional numbers with denominator 70 - For the 1st fraction, since 35 × 2 = 70,
21/35 = 21 × 2/35 × 2 = 42/70 - Likewise, for the 2nd fraction, since 70 × 1 = 70,
49/70 = 49 × 1/70 × 1 = 49/70 - Subtract the two like fractions:
42/70 - 49/70 = 42 - 49/70 = -7/70 - After reducing the fraction, the answer is -1/10
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