Subtract 40/21 from 30/8
1st number: 3 6/8, 2nd number: 1 19/21
30/8 - 40/21 is 155/84.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 21 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 8 × 21 = 168,
30/8 = 30 × 21/8 × 21 = 630/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
40/21 = 40 × 8/21 × 8 = 320/168 - Subtract the two like fractions:
630/168 - 320/168 = 630 - 320/168 = 310/168 - After reducing the fraction, the answer is 155/84
- In mixed form: 171/84
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