Subtract 15/8 from 90/20
1st number: 4 10/20, 2nd number: 1 7/8
90/20 - 15/8 is 21/8.
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,
90/20 = 90 × 2/20 × 2 = 180/40 - Likewise, for the 2nd fraction, since 8 × 5 = 40,
15/8 = 15 × 5/8 × 5 = 75/40 - Subtract the two like fractions:
180/40 - 75/40 = 180 - 75/40 = 105/40 - After reducing the fraction, the answer is 21/8
- In mixed form: 25/8
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