Add 70/21 and 2/42, Solve 3 7/21 + 2/42 as a fraction

Add 70/21 and 2/42

1^st number: 3 7/21, 2^nd number: 2/42

70/21 + 2/42 is 71/21.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 42 is 42

Next, find the equivalent fraction of both fractional numbers with denominator 42
For the 1st fraction, since 21 × 2 = 42,
70/21 = 70 × 2/21 × 2 = 140/42
Likewise, for the 2nd fraction, since 42 × 1 = 42,
2/42 = 2 × 1/42 × 1 = 2/42
Add the two like fractions:
140/42 + 2/42 = 140 + 2/42 = 142/42
142/42 simplified gives 71/21
So, 70/21 + 2/42 = 71/21
In mixed form: 38/21

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