Subtract 36/72 from 21/90
21/90 - 36/72 is -4/15.
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,
36/72 = 36 × 5/72 × 5 = 180/360 - Subtract the two like fractions:
84/360 - 180/360 = 84 - 180/360 = -96/360 - After reducing the fraction, the answer is -4/15
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