Add 21/2 and 42/21
1st number: 10 1/2, 2nd number: 2 0/21
21/2 + 42/21 is 25/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 2 and 21 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 21 × 2 = 42,
42/21 = 42 × 2/21 × 2 = 84/42 - Add the two like fractions:
441/42 + 84/42 = 441 + 84/42 = 525/42 - 525/42 simplified gives 25/2
- So, 21/2 + 42/21 = 25/2
In mixed form: 121/2
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