Subtract 42/18 from 72/90
1st number: 72/90, 2nd number: 2 6/18
72/90 - 42/18 is -23/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 18 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 90 × 1 = 90,
72/90 = 72 × 1/90 × 1 = 72/90 - Likewise, for the 2nd fraction, since 18 × 5 = 90,
42/18 = 42 × 5/18 × 5 = 210/90 - Subtract the two like fractions:
72/90 - 210/90 = 72 - 210/90 = -138/90 - After reducing the fraction, the answer is -23/15
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