Subtract 72/15 from 90/8
1st number: 11 2/8, 2nd number: 4 12/15
90/8 - 72/15 is 129/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 15 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 8 × 15 = 120,
90/8 = 90 × 15/8 × 15 = 1350/120 - Likewise, for the 2nd fraction, since 15 × 8 = 120,
72/15 = 72 × 8/15 × 8 = 576/120 - Subtract the two like fractions:
1350/120 - 576/120 = 1350 - 576/120 = 774/120 - After reducing the fraction, the answer is 129/20
- In mixed form: 69/20
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