Subtract 90/25 from 21/45
1st number: 21/45, 2nd number: 3 15/25
21/45 - 90/25 is -47/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 25 is 225
Next, find the equivalent fraction of both fractional numbers with denominator 225 - For the 1st fraction, since 45 × 5 = 225,
21/45 = 21 × 5/45 × 5 = 105/225 - Likewise, for the 2nd fraction, since 25 × 9 = 225,
90/25 = 90 × 9/25 × 9 = 810/225 - Subtract the two like fractions:
105/225 - 810/225 = 105 - 810/225 = -705/225 - After reducing the fraction, the answer is -47/15
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