Subtract 20/21 from 15/75
15/75 - 20/21 is -79/105.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 75 and 21 is 525
Next, find the equivalent fraction of both fractional numbers with denominator 525 - For the 1st fraction, since 75 × 7 = 525,
15/75 = 15 × 7/75 × 7 = 105/525 - Likewise, for the 2nd fraction, since 21 × 25 = 525,
20/21 = 20 × 25/21 × 25 = 500/525 - Subtract the two like fractions:
105/525 - 500/525 = 105 - 500/525 = -395/525 - After reducing the fraction, the answer is -79/105
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