Subtract 21/12 from 90/30
1st number: 3 0/30, 2nd number: 1 9/12
90/30 - 21/12 is 5/4.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 12 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 30 × 2 = 60,
90/30 = 90 × 2/30 × 2 = 180/60 - Likewise, for the 2nd fraction, since 12 × 5 = 60,
21/12 = 21 × 5/12 × 5 = 105/60 - Subtract the two like fractions:
180/60 - 105/60 = 180 - 105/60 = 75/60 - After reducing the fraction, the answer is 5/4
- In mixed form: 11/4
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