Add 42/21 and 21/5, Solve 2 0/21 + 4 1/5 as a fraction

Add 42/21 and 21/5

1^st number: 2 0/21, 2^nd number: 4 1/5

42/21 + 21/5 is 31/5.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 5 is 105

Next, find the equivalent fraction of both fractional numbers with denominator 105
For the 1st fraction, since 21 × 5 = 105,
42/21 = 42 × 5/21 × 5 = 210/105
Likewise, for the 2nd fraction, since 5 × 21 = 105,
21/5 = 21 × 21/5 × 21 = 441/105
Add the two like fractions:
210/105 + 441/105 = 210 + 441/105 = 651/105
651/105 simplified gives 31/5
So, 42/21 + 21/5 = 31/5
In mixed form: 61/5

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