Subtract 21/3 from 45/90
1st number: 45/90, 2nd number: 7 0/3
45/90 - 21/3 is -13/2.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 3 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 90 × 1 = 90,
45/90 = 45 × 1/90 × 1 = 45/90 - Likewise, for the 2nd fraction, since 3 × 30 = 90,
21/3 = 21 × 30/3 × 30 = 630/90 - Subtract the two like fractions:
45/90 - 630/90 = 45 - 630/90 = -585/90 - After reducing the fraction, the answer is -13/2
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