Add 21/5 and 42/21
1st number: 4 1/5, 2nd number: 2 0/21
21/5 + 42/21 is 31/5.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 5 × 21 = 105,
21/5 = 21 × 21/5 × 21 = 441/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
42/21 = 42 × 5/21 × 5 = 210/105 - Add the two like fractions:
441/105 + 210/105 = 441 + 210/105 = 651/105 - 651/105 simplified gives 31/5
- So, 21/5 + 42/21 = 31/5
In mixed form: 61/5
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