Subtract 90/20 from 20/72
1st number: 20/72, 2nd number: 4 10/20
20/72 - 90/20 is -38/9.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 20 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 72 × 5 = 360,
20/72 = 20 × 5/72 × 5 = 100/360 - Likewise, for the 2nd fraction, since 20 × 18 = 360,
90/20 = 90 × 18/20 × 18 = 1620/360 - Subtract the two like fractions:
100/360 - 1620/360 = 100 - 1620/360 = -1520/360 - After reducing the fraction, the answer is -38/9
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