Subtract 42/15 from 30/20
1st number: 1 10/20, 2nd number: 2 12/15
30/20 - 42/15 is -13/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 15 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 20 × 3 = 60,
30/20 = 30 × 3/20 × 3 = 90/60 - Likewise, for the 2nd fraction, since 15 × 4 = 60,
42/15 = 42 × 4/15 × 4 = 168/60 - Subtract the two like fractions:
90/60 - 168/60 = 90 - 168/60 = -78/60 - After reducing the fraction, the answer is -13/10
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