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

Add 42/2 and 21/5

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

42/2 + 21/5 is 126/5.

Find the least common denominator or LCM of the two denominators:
LCM of 2 and 5 is 10

Next, find the equivalent fraction of both fractional numbers with denominator 10
For the 1st fraction, since 2 × 5 = 10,
42/2 = 42 × 5/2 × 5 = 210/10
Likewise, for the 2nd fraction, since 5 × 2 = 10,
21/5 = 21 × 2/5 × 2 = 42/10
Add the two like fractions:
210/10 + 42/10 = 210 + 42/10 = 252/10
252/10 simplified gives 126/5
So, 42/2 + 21/5 = 126/5
In mixed form: 251/5

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