Subtract 21/35 from 28/70
28/70 - 21/35 is -1/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 35 is 70
Next, find the equivalent fraction of both fractional numbers with denominator 70 - For the 1st fraction, since 70 × 1 = 70,
28/70 = 28 × 1/70 × 1 = 28/70 - Likewise, for the 2nd fraction, since 35 × 2 = 70,
21/35 = 21 × 2/35 × 2 = 42/70 - Subtract the two like fractions:
28/70 - 42/70 = 28 - 42/70 = -14/70 - After reducing the fraction, the answer is -1/5
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