Subtract 20/90 from 42/80
42/80 - 20/90 is 109/360.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 90 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 80 × 9 = 720,
42/80 = 42 × 9/80 × 9 = 378/720 - Likewise, for the 2nd fraction, since 90 × 8 = 720,
20/90 = 20 × 8/90 × 8 = 160/720 - Subtract the two like fractions:
378/720 - 160/720 = 378 - 160/720 = 218/720 - After reducing the fraction, the answer is 109/360
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