Subtract 21/84 from 18/10
1st number: 1 8/10, 2nd number: 21/84
18/10 - 21/84 is 31/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 10 and 84 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 10 × 42 = 420,
18/10 = 18 × 42/10 × 42 = 756/420 - Likewise, for the 2nd fraction, since 84 × 5 = 420,
21/84 = 21 × 5/84 × 5 = 105/420 - Subtract the two like fractions:
756/420 - 105/420 = 756 - 105/420 = 651/420 - After reducing the fraction, the answer is 31/20
- In mixed form: 111/20
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