Subtract 21/10 from 84/18
1st number: 4 12/18, 2nd number: 2 1/10
84/18 - 21/10 is 77/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 10 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 18 × 5 = 90,
84/18 = 84 × 5/18 × 5 = 420/90 - Likewise, for the 2nd fraction, since 10 × 9 = 90,
21/10 = 21 × 9/10 × 9 = 189/90 - Subtract the two like fractions:
420/90 - 189/90 = 420 - 189/90 = 231/90 - After reducing the fraction, the answer is 77/30
- In mixed form: 217/30
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