Subtract 3/40 from 42/12
1st number: 3 6/12, 2nd number: 3/40
42/12 - 3/40 is 137/40.
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,
42/12 = 42 × 10/12 × 10 = 420/120 - Likewise, for the 2nd fraction, since 40 × 3 = 120,
3/40 = 3 × 3/40 × 3 = 9/120 - Subtract the two like fractions:
420/120 - 9/120 = 420 - 9/120 = 411/120 - After reducing the fraction, the answer is 137/40
- In mixed form: 317/40
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