Subtract 20/45 from 42/18
1st number: 2 6/18, 2nd number: 20/45
42/18 - 20/45 is 17/9.
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,
20/45 = 20 × 2/45 × 2 = 40/90 - Subtract the two like fractions:
210/90 - 40/90 = 210 - 40/90 = 170/90 - After reducing the fraction, the answer is 17/9
- In mixed form: 18/9
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