Subtract 20/8 from 30/84
1st number: 30/84, 2nd number: 2 4/8
30/84 - 20/8 is -15/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 8 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 84 × 2 = 168,
30/84 = 30 × 2/84 × 2 = 60/168 - Likewise, for the 2nd fraction, since 8 × 21 = 168,
20/8 = 20 × 21/8 × 21 = 420/168 - Subtract the two like fractions:
60/168 - 420/168 = 60 - 420/168 = -360/168 - After reducing the fraction, the answer is -15/7
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