Subtract 18/72 from 7/45
7/45 - 18/72 is -17/180.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 72 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 45 × 8 = 360,
7/45 = 7 × 8/45 × 8 = 56/360 - Likewise, for the 2nd fraction, since 72 × 5 = 360,
18/72 = 18 × 5/72 × 5 = 90/360 - Subtract the two like fractions:
56/360 - 90/360 = 56 - 90/360 = -34/360 - After reducing the fraction, the answer is -17/180
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