Subtract 18/21 from 20/25
20/25 - 18/21 is -2/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 25 and 21 is 525
Next, find the equivalent fraction of both fractional numbers with denominator 525 - For the 1st fraction, since 25 × 21 = 525,
20/25 = 20 × 21/25 × 21 = 420/525 - Likewise, for the 2nd fraction, since 21 × 25 = 525,
18/21 = 18 × 25/21 × 25 = 450/525 - Subtract the two like fractions:
420/525 - 450/525 = 420 - 450/525 = -30/525 - After reducing the fraction, the answer is -2/35
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