Subtract 90/50 from 21/20
1st number: 1 1/20, 2nd number: 1 40/50
21/20 - 90/50 is -3/4.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 50 is 100
Next, find the equivalent fraction of both fractional numbers with denominator 100 - For the 1st fraction, since 20 × 5 = 100,
21/20 = 21 × 5/20 × 5 = 105/100 - Likewise, for the 2nd fraction, since 50 × 2 = 100,
90/50 = 90 × 2/50 × 2 = 180/100 - Subtract the two like fractions:
105/100 - 180/100 = 105 - 180/100 = -75/100 - After reducing the fraction, the answer is -3/4
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