Subtract 20/18 from 72/90
1st number: 72/90, 2nd number: 1 2/18
72/90 - 20/18 is -14/45.
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,
20/18 = 20 × 5/18 × 5 = 100/90 - Subtract the two like fractions:
72/90 - 100/90 = 72 - 100/90 = -28/90 - After reducing the fraction, the answer is -14/45
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