Subtract 90/25 from 7/21
1st number: 7/21, 2nd number: 3 15/25
7/21 - 90/25 is -49/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 25 is 525
Next, find the equivalent fraction of both fractional numbers with denominator 525 - For the 1st fraction, since 21 × 25 = 525,
7/21 = 7 × 25/21 × 25 = 175/525 - Likewise, for the 2nd fraction, since 25 × 21 = 525,
90/25 = 90 × 21/25 × 21 = 1890/525 - Subtract the two like fractions:
175/525 - 1890/525 = 175 - 1890/525 = -1715/525 - After reducing the fraction, the answer is -49/15
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