Subtract 45/90 from 72/20
1st number: 3 12/20, 2nd number: 45/90
72/20 - 45/90 is 31/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 90 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 20 × 9 = 180,
72/20 = 72 × 9/20 × 9 = 648/180 - Likewise, for the 2nd fraction, since 90 × 2 = 180,
45/90 = 45 × 2/90 × 2 = 90/180 - Subtract the two like fractions:
648/180 - 90/180 = 648 - 90/180 = 558/180 - After reducing the fraction, the answer is 31/10
- In mixed form: 31/10
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