Add 4/10 and 42/21, Solve 4/10 + 2 0/21 as a fraction

Add 4/10 and 42/21

1^st number: 4/10, 2^nd number: 2 0/21

4/10 + 42/21 is 12/5.

Find the least common denominator or LCM of the two denominators:
LCM of 10 and 21 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 10 × 21 = 210,
4/10 = 4 × 21/10 × 21 = 84/210
Likewise, for the 2nd fraction, since 21 × 10 = 210,
42/21 = 42 × 10/21 × 10 = 420/210
Add the two like fractions:
84/210 + 420/210 = 84 + 420/210 = 504/210
504/210 simplified gives 12/5
So, 4/10 + 42/21 = 12/5
In mixed form: 22/5

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