Subtract 45/15 from 18/20
1st number: 18/20, 2nd number: 3 0/15
18/20 - 45/15 is -21/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 15 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 20 × 3 = 60,
18/20 = 18 × 3/20 × 3 = 54/60 - Likewise, for the 2nd fraction, since 15 × 4 = 60,
45/15 = 45 × 4/15 × 4 = 180/60 - Subtract the two like fractions:
54/60 - 180/60 = 54 - 180/60 = -126/60 - After reducing the fraction, the answer is -21/10
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