Subtract 42/15 from 3/40
1st number: 3/40, 2nd number: 2 12/15
3/40 - 42/15 is -109/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 15 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 40 × 3 = 120,
3/40 = 3 × 3/40 × 3 = 9/120 - Likewise, for the 2nd fraction, since 15 × 8 = 120,
42/15 = 42 × 8/15 × 8 = 336/120 - Subtract the two like fractions:
9/120 - 336/120 = 9 - 336/120 = -327/120 - After reducing the fraction, the answer is -109/40
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