Subtract 90/42 from 18/20
1st number: 18/20, 2nd number: 2 6/42
18/20 - 90/42 is -87/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 42 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
18/20 = 18 × 21/20 × 21 = 378/420 - Likewise, for the 2nd fraction, since 42 × 10 = 420,
90/42 = 90 × 10/42 × 10 = 900/420 - Subtract the two like fractions:
378/420 - 900/420 = 378 - 900/420 = -522/420 - After reducing the fraction, the answer is -87/70
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