Subtract 42/9 from 90/20
1st number: 4 10/20, 2nd number: 4 6/9
90/20 - 42/9 is -1/6.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 9 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 20 × 9 = 180,
90/20 = 90 × 9/20 × 9 = 810/180 - Likewise, for the 2nd fraction, since 9 × 20 = 180,
42/9 = 42 × 20/9 × 20 = 840/180 - Subtract the two like fractions:
810/180 - 840/180 = 810 - 840/180 = -30/180 - After reducing the fraction, the answer is -1/6
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