Subtract 35/40 from 42/72
42/72 - 35/40 is -7/24.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 40 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 72 × 5 = 360,
42/72 = 42 × 5/72 × 5 = 210/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
35/40 = 35 × 9/40 × 9 = 315/360 - Subtract the two like fractions:
210/360 - 315/360 = 210 - 315/360 = -105/360 - After reducing the fraction, the answer is -7/24
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