Subtract 42/18 from 21/10
1st number: 2 1/10, 2nd number: 2 6/18
21/10 - 42/18 is -7/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 10 and 18 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 10 × 9 = 90,
21/10 = 21 × 9/10 × 9 = 189/90 - Likewise, for the 2nd fraction, since 18 × 5 = 90,
42/18 = 42 × 5/18 × 5 = 210/90 - Subtract the two like fractions:
189/90 - 210/90 = 189 - 210/90 = -21/90 - After reducing the fraction, the answer is -7/30
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