Subtract 9/10 from 21/72
21/72 - 9/10 is -73/120.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 10 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 72 × 5 = 360,
21/72 = 21 × 5/72 × 5 = 105/360 - Likewise, for the 2nd fraction, since 10 × 36 = 360,
9/10 = 9 × 36/10 × 36 = 324/360 - Subtract the two like fractions:
105/360 - 324/360 = 105 - 324/360 = -219/360 - After reducing the fraction, the answer is -73/120
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