Subtract 30/45 from 18/72
18/72 - 30/45 is -5/12.
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,
18/72 = 18 × 5/72 × 5 = 90/360 - Likewise, for the 2nd fraction, since 45 × 8 = 360,
30/45 = 30 × 8/45 × 8 = 240/360 - Subtract the two like fractions:
90/360 - 240/360 = 90 - 240/360 = -150/360 - After reducing the fraction, the answer is -5/12
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