Subtract 72/40 from 8/18
1st number: 8/18, 2nd number: 1 32/40
8/18 - 72/40 is -61/45.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 40 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 18 × 20 = 360,
8/18 = 8 × 20/18 × 20 = 160/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
72/40 = 72 × 9/40 × 9 = 648/360 - Subtract the two like fractions:
160/360 - 648/360 = 160 - 648/360 = -488/360 - After reducing the fraction, the answer is -61/45
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