Subtract 30/8 from 40/21
1st number: 1 19/21, 2nd number: 3 6/8
40/21 - 30/8 is -155/84.
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,
40/21 = 40 × 8/21 × 8 = 320/168 - Likewise, for the 2nd fraction, since 8 × 21 = 168,
30/8 = 30 × 21/8 × 21 = 630/168 - Subtract the two like fractions:
320/168 - 630/168 = 320 - 630/168 = -310/168 - After reducing the fraction, the answer is -155/84
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