Subtract 42/21 from 18/25
1st number: 18/25, 2nd number: 2 0/21
18/25 - 42/21 is -32/25.
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,
18/25 = 18 × 21/25 × 21 = 378/525 - Likewise, for the 2nd fraction, since 21 × 25 = 525,
42/21 = 42 × 25/21 × 25 = 1050/525 - Subtract the two like fractions:
378/525 - 1050/525 = 378 - 1050/525 = -672/525 - After reducing the fraction, the answer is -32/25
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