Subtract 84/72 from 21/90
1st number: 21/90, 2nd number: 1 12/72
21/90 - 84/72 is -14/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 72 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 90 × 4 = 360,
21/90 = 21 × 4/90 × 4 = 84/360 - Likewise, for the 2nd fraction, since 72 × 5 = 360,
84/72 = 84 × 5/72 × 5 = 420/360 - Subtract the two like fractions:
84/360 - 420/360 = 84 - 420/360 = -336/360 - After reducing the fraction, the answer is -14/15
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