Subtract 90/72 from 18/15
1st number: 1 3/15, 2nd number: 1 18/72
18/15 - 90/72 is -1/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 72 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 15 × 24 = 360,
18/15 = 18 × 24/15 × 24 = 432/360 - Likewise, for the 2nd fraction, since 72 × 5 = 360,
90/72 = 90 × 5/72 × 5 = 450/360 - Subtract the two like fractions:
432/360 - 450/360 = 432 - 450/360 = -18/360 - After reducing the fraction, the answer is -1/20
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