Subtract 9/28 from 21/70
21/70 - 9/28 is -3/140.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 28 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 70 × 2 = 140,
21/70 = 21 × 2/70 × 2 = 42/140 - Likewise, for the 2nd fraction, since 28 × 5 = 140,
9/28 = 9 × 5/28 × 5 = 45/140 - Subtract the two like fractions:
42/140 - 45/140 = 42 - 45/140 = -3/140
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