Subtract 90/20 from 42/15
1st number: 2 12/15, 2nd number: 4 10/20
42/15 - 90/20 is -17/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 20 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 15 × 4 = 60,
42/15 = 42 × 4/15 × 4 = 168/60 - Likewise, for the 2nd fraction, since 20 × 3 = 60,
90/20 = 90 × 3/20 × 3 = 270/60 - Subtract the two like fractions:
168/60 - 270/60 = 168 - 270/60 = -102/60 - After reducing the fraction, the answer is -17/10
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