Subtract 21/45 from 42/18
1st number: 2 6/18, 2nd number: 21/45
42/18 - 21/45 is 28/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 45 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 18 × 5 = 90,
42/18 = 42 × 5/18 × 5 = 210/90 - Likewise, for the 2nd fraction, since 45 × 2 = 90,
21/45 = 21 × 2/45 × 2 = 42/90 - Subtract the two like fractions:
210/90 - 42/90 = 210 - 42/90 = 168/90 - After reducing the fraction, the answer is 28/15
- In mixed form: 113/15
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