Subtract 90/20 from 21/8
1st number: 2 5/8, 2nd number: 4 10/20
21/8 - 90/20 is -15/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 20 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 8 × 5 = 40,
21/8 = 21 × 5/8 × 5 = 105/40 - Likewise, for the 2nd fraction, since 20 × 2 = 40,
90/20 = 90 × 2/20 × 2 = 180/40 - Subtract the two like fractions:
105/40 - 180/40 = 105 - 180/40 = -75/40 - After reducing the fraction, the answer is -15/8
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