Subtract 21/70 from 7/28
7/28 - 21/70 is -1/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 70 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 28 × 5 = 140,
7/28 = 7 × 5/28 × 5 = 35/140 - Likewise, for the 2nd fraction, since 70 × 2 = 140,
21/70 = 21 × 2/70 × 2 = 42/140 - Subtract the two like fractions:
35/140 - 42/140 = 35 - 42/140 = -7/140 - After reducing the fraction, the answer is -1/20
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