Subtract 42/72 from 20/45
20/45 - 42/72 is -5/36.
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,
20/45 = 20 × 8/45 × 8 = 160/360 - Likewise, for the 2nd fraction, since 72 × 5 = 360,
42/72 = 42 × 5/72 × 5 = 210/360 - Subtract the two like fractions:
160/360 - 210/360 = 160 - 210/360 = -50/360 - After reducing the fraction, the answer is -5/36
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