Subtract 20/18 from 40/45
1st number: 40/45, 2nd number: 1 2/18
40/45 - 20/18 is -2/9.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 18 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 45 × 2 = 90,
40/45 = 40 × 2/45 × 2 = 80/90 - Likewise, for the 2nd fraction, since 18 × 5 = 90,
20/18 = 20 × 5/18 × 5 = 100/90 - Subtract the two like fractions:
80/90 - 100/90 = 80 - 100/90 = -20/90 - After reducing the fraction, the answer is -2/9
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