Add 2/5 and 70/21, Solve 2/5 + 3 7/21 as a fraction

Add 2/5 and 70/21

1^st number: 2/5, 2^nd number: 3 7/21

2/5 + 70/21 is 56/15.

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

Next, find the equivalent fraction of both fractional numbers with denominator 105
For the 1st fraction, since 5 × 21 = 105,
2/5 = 2 × 21/5 × 21 = 42/105
Likewise, for the 2nd fraction, since 21 × 5 = 105,
70/21 = 70 × 5/21 × 5 = 350/105
Add the two like fractions:
42/105 + 350/105 = 42 + 350/105 = 392/105
392/105 simplified gives 56/15
So, 2/5 + 70/21 = 56/15
In mixed form: 311/15

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