Subtract 40/21 from 9/10
1st number: 9/10, 2nd number: 1 19/21
9/10 - 40/21 is -211/210.
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,
40/21 = 40 × 10/21 × 10 = 400/210 - Subtract the two like fractions:
189/210 - 400/210 = 189 - 400/210 = -211/210
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