Subtract 75/90 from 42/72
42/72 - 75/90 is -1/4.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 90 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 90 × 4 = 360,
75/90 = 75 × 4/90 × 4 = 300/360 - Subtract the two like fractions:
210/360 - 300/360 = 210 - 300/360 = -90/360 - After reducing the fraction, the answer is -1/4
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