Add 70/21 and 70/9, Solve 3 7/21 + 7 7/9 as a fraction

Add 70/21 and 70/9

1^st number: 3 7/21, 2^nd number: 7 7/9

70/21 + 70/9 is 100/9.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 9 is 63

Next, find the equivalent fraction of both fractional numbers with denominator 63
For the 1st fraction, since 21 × 3 = 63,
70/21 = 70 × 3/21 × 3 = 210/63
Likewise, for the 2nd fraction, since 9 × 7 = 63,
70/9 = 70 × 7/9 × 7 = 490/63
Add the two like fractions:
210/63 + 490/63 = 210 + 490/63 = 700/63
700/63 simplified gives 100/9
So, 70/21 + 70/9 = 100/9
In mixed form: 111/9

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