Subtract 45/3 from 90/20
1st number: 4 10/20, 2nd number: 15 0/3
90/20 - 45/3 is -21/2.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 3 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 20 × 3 = 60,
90/20 = 90 × 3/20 × 3 = 270/60 - Likewise, for the 2nd fraction, since 3 × 20 = 60,
45/3 = 45 × 20/3 × 20 = 900/60 - Subtract the two like fractions:
270/60 - 900/60 = 270 - 900/60 = -630/60 - After reducing the fraction, the answer is -21/2
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