Subtract 18/10 from 21/45
1st number: 21/45, 2nd number: 1 8/10
21/45 - 18/10 is -4/3.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 10 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 45 × 2 = 90,
21/45 = 21 × 2/45 × 2 = 42/90 - Likewise, for the 2nd fraction, since 10 × 9 = 90,
18/10 = 18 × 9/10 × 9 = 162/90 - Subtract the two like fractions:
42/90 - 162/90 = 42 - 162/90 = -120/90 - After reducing the fraction, the answer is -4/3
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