Subtract 45/20 from 18/84
1st number: 18/84, 2nd number: 2 5/20
18/84 - 45/20 is -57/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 84 × 5 = 420,
18/84 = 18 × 5/84 × 5 = 90/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
45/20 = 45 × 21/20 × 21 = 945/420 - Subtract the two like fractions:
90/420 - 945/420 = 90 - 945/420 = -855/420 - After reducing the fraction, the answer is -57/28
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