Subtract 21/7 from 21/10
1st number: 2 1/10, 2nd number: 3 0/7
21/10 - 21/7 is -9/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 10 and 7 is 70
Next, find the equivalent fraction of both fractional numbers with denominator 70 - For the 1st fraction, since 10 × 7 = 70,
21/10 = 21 × 7/10 × 7 = 147/70 - Likewise, for the 2nd fraction, since 7 × 10 = 70,
21/7 = 21 × 10/7 × 10 = 210/70 - Subtract the two like fractions:
147/70 - 210/70 = 147 - 210/70 = -63/70 - After reducing the fraction, the answer is -9/10
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