Subtract 45/20 from 90/42
1st number: 2 6/42, 2nd number: 2 5/20
90/42 - 45/20 is -3/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 42 × 10 = 420,
90/42 = 90 × 10/42 × 10 = 900/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
45/20 = 45 × 21/20 × 21 = 945/420 - Subtract the two like fractions:
900/420 - 945/420 = 900 - 945/420 = -45/420 - After reducing the fraction, the answer is -3/28
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