Subtract 9/40 from 21/10
1st number: 2 1/10, 2nd number: 9/40
21/10 - 9/40 is 15/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 10 and 40 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 10 × 4 = 40,
21/10 = 21 × 4/10 × 4 = 84/40 - Likewise, for the 2nd fraction, since 40 × 1 = 40,
9/40 = 9 × 1/40 × 1 = 9/40 - Subtract the two like fractions:
84/40 - 9/40 = 84 - 9/40 = 75/40 - After reducing the fraction, the answer is 15/8
- In mixed form: 17/8
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