Add 42/21 and 81/8
1st number: 2 0/21, 2nd number: 10 1/8
42/21 + 81/8 is 97/8.
Steps for adding 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,
42/21 = 42 × 8/21 × 8 = 336/168 - Likewise, for the 2nd fraction, since 8 × 21 = 168,
81/8 = 81 × 21/8 × 21 = 1701/168 - Add the two like fractions:
336/168 + 1701/168 = 336 + 1701/168 = 2037/168 - 2037/168 simplified gives 97/8
- So, 42/21 + 81/8 = 97/8
In mixed form: 121/8
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