Subtract 21/90 from 10/72
10/72 - 21/90 is -17/180.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 90 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 72 × 5 = 360,
10/72 = 10 × 5/72 × 5 = 50/360 - Likewise, for the 2nd fraction, since 90 × 4 = 360,
21/90 = 21 × 4/90 × 4 = 84/360 - Subtract the two like fractions:
50/360 - 84/360 = 50 - 84/360 = -34/360 - After reducing the fraction, the answer is -17/180
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