Subtract 72/18 from 90/42
1st number: 2 6/42, 2nd number: 4 0/18
90/42 - 72/18 is -13/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 18 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 42 × 3 = 126,
90/42 = 90 × 3/42 × 3 = 270/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
72/18 = 72 × 7/18 × 7 = 504/126 - Subtract the two like fractions:
270/126 - 504/126 = 270 - 504/126 = -234/126 - After reducing the fraction, the answer is -13/7
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