Subtract 42/80 from 90/20
1st number: 4 10/20, 2nd number: 42/80
90/20 - 42/80 is 159/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 80 is 80
Next, find the equivalent fraction of both fractional numbers with denominator 80 - For the 1st fraction, since 20 × 4 = 80,
90/20 = 90 × 4/20 × 4 = 360/80 - Likewise, for the 2nd fraction, since 80 × 1 = 80,
42/80 = 42 × 1/80 × 1 = 42/80 - Subtract the two like fractions:
360/80 - 42/80 = 360 - 42/80 = 318/80 - After reducing the fraction, the answer is 159/40
- In mixed form: 339/40
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