Subtract 90/30 from 21/20
1st number: 1 1/20, 2nd number: 3 0/30
21/20 - 90/30 is -39/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 30 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 20 × 3 = 60,
21/20 = 21 × 3/20 × 3 = 63/60 - Likewise, for the 2nd fraction, since 30 × 2 = 60,
90/30 = 90 × 2/30 × 2 = 180/60 - Subtract the two like fractions:
63/60 - 180/60 = 63 - 180/60 = -117/60 - After reducing the fraction, the answer is -39/20
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