Subtract 9/8 from 72/20
1st number: 3 12/20, 2nd number: 1 1/8
72/20 - 9/8 is 99/40.
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,
72/20 = 72 × 2/20 × 2 = 144/40 - Likewise, for the 2nd fraction, since 8 × 5 = 40,
9/8 = 9 × 5/8 × 5 = 45/40 - Subtract the two like fractions:
144/40 - 45/40 = 144 - 45/40 = 99/40 - In mixed form: 219/40
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