Subtract 9/40 from 21/12
1st number: 1 9/12, 2nd number: 9/40
21/12 - 9/40 is 61/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 40 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 12 × 10 = 120,
21/12 = 21 × 10/12 × 10 = 210/120 - Likewise, for the 2nd fraction, since 40 × 3 = 120,
9/40 = 9 × 3/40 × 3 = 27/120 - Subtract the two like fractions:
210/120 - 27/120 = 210 - 27/120 = 183/120 - After reducing the fraction, the answer is 61/40
- In mixed form: 121/40
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