Subtract 90/72 from 18/20
1st number: 18/20, 2nd number: 1 18/72
18/20 - 90/72 is -7/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 72 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 20 × 18 = 360,
18/20 = 18 × 18/20 × 18 = 324/360 - Likewise, for the 2nd fraction, since 72 × 5 = 360,
90/72 = 90 × 5/72 × 5 = 450/360 - Subtract the two like fractions:
324/360 - 450/360 = 324 - 450/360 = -126/360 - After reducing the fraction, the answer is -7/20
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