Subtract 42/45 from 28/20
1st number: 1 8/20, 2nd number: 42/45
28/20 - 42/45 is 7/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 45 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 20 × 9 = 180,
28/20 = 28 × 9/20 × 9 = 252/180 - Likewise, for the 2nd fraction, since 45 × 4 = 180,
42/45 = 42 × 4/45 × 4 = 168/180 - Subtract the two like fractions:
252/180 - 168/180 = 252 - 168/180 = 84/180 - After reducing the fraction, the answer is 7/15
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