Subtract 20/40 from 72/18
1st number: 4 0/18, 2nd number: 20/40
72/18 - 20/40 is 7/2.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 40 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 18 × 20 = 360,
72/18 = 72 × 20/18 × 20 = 1440/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
20/40 = 20 × 9/40 × 9 = 180/360 - Subtract the two like fractions:
1440/360 - 180/360 = 1440 - 180/360 = 1260/360 - After reducing the fraction, the answer is 7/2
- In mixed form: 31/2
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