Add 70/20 and 8/21, Solve 3 10/20 + 8/21 as a fraction

Add 70/20 and 8/21

1^st number: 3 10/20, 2^nd number: 8/21

70/20 + 8/21 is 163/42.

Find the least common denominator or LCM of the two denominators:
LCM of 20 and 21 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 20 × 21 = 420,
70/20 = 70 × 21/20 × 21 = 1470/420
Likewise, for the 2nd fraction, since 21 × 20 = 420,
8/21 = 8 × 20/21 × 20 = 160/420
Add the two like fractions:
1470/420 + 160/420 = 1470 + 160/420 = 1630/420
1630/420 simplified gives 163/42
So, 70/20 + 8/21 = 163/42
In mixed form: 337/42

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