Subtract 45/40 from 18/84
1st number: 18/84, 2nd number: 1 5/40
18/84 - 45/40 is -51/56.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 84 × 10 = 840,
18/84 = 18 × 10/84 × 10 = 180/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
45/40 = 45 × 21/40 × 21 = 945/840 - Subtract the two like fractions:
180/840 - 945/840 = 180 - 945/840 = -765/840 - After reducing the fraction, the answer is -51/56
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