Subtract 3/90 from 42/20
1st number: 2 2/20, 2nd number: 3/90
42/20 - 3/90 is 31/15.
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,
42/20 = 42 × 9/20 × 9 = 378/180 - Likewise, for the 2nd fraction, since 90 × 2 = 180,
3/90 = 3 × 2/90 × 2 = 6/180 - Subtract the two like fractions:
378/180 - 6/180 = 378 - 6/180 = 372/180 - After reducing the fraction, the answer is 31/15
- In mixed form: 21/15
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