Subtract 90/8 from 15/20
1st number: 15/20, 2nd number: 11 2/8
15/20 - 90/8 is -21/2.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 8 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 20 × 2 = 40,
15/20 = 15 × 2/20 × 2 = 30/40 - Likewise, for the 2nd fraction, since 8 × 5 = 40,
90/8 = 90 × 5/8 × 5 = 450/40 - Subtract the two like fractions:
30/40 - 450/40 = 30 - 450/40 = -420/40 - After reducing the fraction, the answer is -21/2
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