Subtract 21/40 from 1/72
1/72 - 21/40 is -23/45.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 40 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 72 × 5 = 360,
1/72 = 1 × 5/72 × 5 = 5/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
21/40 = 21 × 9/40 × 9 = 189/360 - Subtract the two like fractions:
5/360 - 189/360 = 5 - 189/360 = -184/360 - After reducing the fraction, the answer is -23/45
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