Subtract 1/40 from 21/12
1st number: 1 9/12, 2nd number: 1/40
21/12 - 1/40 is 69/40.
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,
1/40 = 1 × 3/40 × 3 = 3/120 - Subtract the two like fractions:
210/120 - 3/120 = 210 - 3/120 = 207/120 - After reducing the fraction, the answer is 69/40
- In mixed form: 129/40
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