Add 21/70 and 84/42, Solve 21/70 + 2 0/42 as a fraction

Add 21/70 and 84/42

1^st number: 21/70, 2^nd number: 2 0/42

21/70 + 84/42 is 23/10.

Find the least common denominator or LCM of the two denominators:
LCM of 70 and 42 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 70 × 3 = 210,
21/70 = 21 × 3/70 × 3 = 63/210
Likewise, for the 2nd fraction, since 42 × 5 = 210,
84/42 = 84 × 5/42 × 5 = 420/210
Add the two like fractions:
63/210 + 420/210 = 63 + 420/210 = 483/210
483/210 simplified gives 23/10
So, 21/70 + 84/42 = 23/10
In mixed form: 23/10

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