Add 7/15 and 70/21, Solve 7/15 + 3 7/21 as a fraction

Add 7/15 and 70/21

1^st number: 7/15, 2^nd number: 3 7/21

7/15 + 70/21 is 19/5.

Find the least common denominator or LCM of the two denominators:
LCM of 15 and 21 is 105

Next, find the equivalent fraction of both fractional numbers with denominator 105
For the 1st fraction, since 15 × 7 = 105,
7/15 = 7 × 7/15 × 7 = 49/105
Likewise, for the 2nd fraction, since 21 × 5 = 105,
70/21 = 70 × 5/21 × 5 = 350/105
Add the two like fractions:
49/105 + 350/105 = 49 + 350/105 = 399/105
399/105 simplified gives 19/5
So, 7/15 + 70/21 = 19/5
In mixed form: 34/5

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