Subtract 30/25 from 21/18
1st number: 1 3/18, 2nd number: 1 5/25
21/18 - 30/25 is -1/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 25 is 450
Next, find the equivalent fraction of both fractional numbers with denominator 450 - For the 1st fraction, since 18 × 25 = 450,
21/18 = 21 × 25/18 × 25 = 525/450 - Likewise, for the 2nd fraction, since 25 × 18 = 450,
30/25 = 30 × 18/25 × 18 = 540/450 - Subtract the two like fractions:
525/450 - 540/450 = 525 - 540/450 = -15/450 - After reducing the fraction, the answer is -1/30
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