Subtract 45/15 from 81/72
1st number: 1 9/72, 2nd number: 3 0/15
81/72 - 45/15 is -15/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 15 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 72 × 5 = 360,
81/72 = 81 × 5/72 × 5 = 405/360 - Likewise, for the 2nd fraction, since 15 × 24 = 360,
45/15 = 45 × 24/15 × 24 = 1080/360 - Subtract the two like fractions:
405/360 - 1080/360 = 405 - 1080/360 = -675/360 - After reducing the fraction, the answer is -15/8
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