Subtract 21/8 from 90/12
1st number: 7 6/12, 2nd number: 2 5/8
90/12 - 21/8 is 39/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 8 is 24
Next, find the equivalent fraction of both fractional numbers with denominator 24 - For the 1st fraction, since 12 × 2 = 24,
90/12 = 90 × 2/12 × 2 = 180/24 - Likewise, for the 2nd fraction, since 8 × 3 = 24,
21/8 = 21 × 3/8 × 3 = 63/24 - Subtract the two like fractions:
180/24 - 63/24 = 180 - 63/24 = 117/24 - After reducing the fraction, the answer is 39/8
- In mixed form: 47/8
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