Subtract 21/10 from 28/20
1st number: 1 8/20, 2nd number: 2 1/10
28/20 - 21/10 is -7/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 10 is 20
Next, find the equivalent fraction of both fractional numbers with denominator 20 - For the 1st fraction, since 20 × 1 = 20,
28/20 = 28 × 1/20 × 1 = 28/20 - Likewise, for the 2nd fraction, since 10 × 2 = 20,
21/10 = 21 × 2/10 × 2 = 42/20 - Subtract the two like fractions:
28/20 - 42/20 = 28 - 42/20 = -14/20 - After reducing the fraction, the answer is -7/10
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