Add 70/21 and 12/5, Solve 3 7/21 + 2 2/5 as a fraction

Add 70/21 and 12/5

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

70/21 + 12/5 is 86/15.

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

Next, find the equivalent fraction of both fractional numbers with denominator 105
For the 1st fraction, since 21 × 5 = 105,
70/21 = 70 × 5/21 × 5 = 350/105
Likewise, for the 2nd fraction, since 5 × 21 = 105,
12/5 = 12 × 21/5 × 21 = 252/105
Add the two like fractions:
350/105 + 252/105 = 350 + 252/105 = 602/105
602/105 simplified gives 86/15
So, 70/21 + 12/5 = 86/15
In mixed form: 511/15

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