Add 21/2 and 81/42
1st number: 10 1/2, 2nd number: 1 39/42
21/2 + 81/42 is 87/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 2 and 42 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 2 × 21 = 42,
21/2 = 21 × 21/2 × 21 = 441/42 - Likewise, for the 2nd fraction, since 42 × 1 = 42,
81/42 = 81 × 1/42 × 1 = 81/42 - Add the two like fractions:
441/42 + 81/42 = 441 + 81/42 = 522/42 - 522/42 simplified gives 87/7
- So, 21/2 + 81/42 = 87/7
In mixed form: 123/7
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