Subtract 42/20 from 72/18
1st number: 4 0/18, 2nd number: 2 2/20
72/18 - 42/20 is 19/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 20 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 18 × 10 = 180,
72/18 = 72 × 10/18 × 10 = 720/180 - Likewise, for the 2nd fraction, since 20 × 9 = 180,
42/20 = 42 × 9/20 × 9 = 378/180 - Subtract the two like fractions:
720/180 - 378/180 = 720 - 378/180 = 342/180 - After reducing the fraction, the answer is 19/10
- In mixed form: 19/10
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