Subtract 90/75 from 7/21
1st number: 7/21, 2nd number: 1 15/75
7/21 - 90/75 is -13/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 75 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 75 × 7 = 525,
90/75 = 90 × 7/75 × 7 = 630/525 - Subtract the two like fractions:
175/525 - 630/525 = 175 - 630/525 = -455/525 - After reducing the fraction, the answer is -13/15
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