Subtract 9/10 from 10/21
10/21 - 9/10 is -89/210.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 10 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 21 × 10 = 210,
10/21 = 10 × 10/21 × 10 = 100/210 - Likewise, for the 2nd fraction, since 10 × 21 = 210,
9/10 = 9 × 21/10 × 21 = 189/210 - Subtract the two like fractions:
100/210 - 189/210 = 100 - 189/210 = -89/210
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