Subtract 20/8 from 84/21
1st number: 4 0/21, 2nd number: 2 4/8
84/21 - 20/8 is 3/2.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 8 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 21 × 8 = 168,
84/21 = 84 × 8/21 × 8 = 672/168 - Likewise, for the 2nd fraction, since 8 × 21 = 168,
20/8 = 20 × 21/8 × 21 = 420/168 - Subtract the two like fractions:
672/168 - 420/168 = 672 - 420/168 = 252/168 - After reducing the fraction, the answer is 3/2
- In mixed form: 11/2
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