Subtract 9/10 from 21/28
21/28 - 9/10 is -3/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 10 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 28 × 5 = 140,
21/28 = 21 × 5/28 × 5 = 105/140 - Likewise, for the 2nd fraction, since 10 × 14 = 140,
9/10 = 9 × 14/10 × 14 = 126/140 - Subtract the two like fractions:
105/140 - 126/140 = 105 - 126/140 = -21/140 - After reducing the fraction, the answer is -3/20
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