Subtract 21/12 from 90/18
1st number: 5 0/18, 2nd number: 1 9/12
90/18 - 21/12 is 13/4.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 12 is 36
Next, find the equivalent fraction of both fractional numbers with denominator 36 - For the 1st fraction, since 18 × 2 = 36,
90/18 = 90 × 2/18 × 2 = 180/36 - Likewise, for the 2nd fraction, since 12 × 3 = 36,
21/12 = 21 × 3/12 × 3 = 63/36 - Subtract the two like fractions:
180/36 - 63/36 = 180 - 63/36 = 117/36 - After reducing the fraction, the answer is 13/4
- In mixed form: 31/4
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