Subtract 9/10 from 21/70
21/70 - 9/10 is -3/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 10 is 70
Next, find the equivalent fraction of both fractional numbers with denominator 70 - For the 1st fraction, since 70 × 1 = 70,
21/70 = 21 × 1/70 × 1 = 21/70 - Likewise, for the 2nd fraction, since 10 × 7 = 70,
9/10 = 9 × 7/10 × 7 = 63/70 - Subtract the two like fractions:
21/70 - 63/70 = 21 - 63/70 = -42/70 - After reducing the fraction, the answer is -3/5
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