Subtract 7/21 from 9/10
9/10 - 7/21 is 17/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 10 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 10 × 21 = 210,
9/10 = 9 × 21/10 × 21 = 189/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
7/21 = 7 × 10/21 × 10 = 70/210 - Subtract the two like fractions:
189/210 - 70/210 = 189 - 70/210 = 119/210 - After reducing the fraction, the answer is 17/30
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