Subtract 21/45 from 3/72
3/72 - 21/45 is -17/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 45 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 72 × 5 = 360,
3/72 = 3 × 5/72 × 5 = 15/360 - Likewise, for the 2nd fraction, since 45 × 8 = 360,
21/45 = 21 × 8/45 × 8 = 168/360 - Subtract the two like fractions:
15/360 - 168/360 = 15 - 168/360 = -153/360 - After reducing the fraction, the answer is -17/40
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