Subtract 21/18 from 25/45
1st number: 25/45, 2nd number: 1 3/18
25/45 - 21/18 is -11/18.
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,
25/45 = 25 × 2/45 × 2 = 50/90 - Likewise, for the 2nd fraction, since 18 × 5 = 90,
21/18 = 21 × 5/18 × 5 = 105/90 - Subtract the two like fractions:
50/90 - 105/90 = 50 - 105/90 = -55/90 - After reducing the fraction, the answer is -11/18
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