Add 28/20 and 70/42, Solve 1 8/20 + 1 28/42 as a fraction

Add 28/20 and 70/42

1^st number: 1 8/20, 2^nd number: 1 28/42

28/20 + 70/42 is 46/15.

Find the least common denominator or LCM of the two denominators:
LCM of 20 and 42 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 20 × 21 = 420,
28/20 = 28 × 21/20 × 21 = 588/420
Likewise, for the 2nd fraction, since 42 × 10 = 420,
70/42 = 70 × 10/42 × 10 = 700/420
Add the two like fractions:
588/420 + 700/420 = 588 + 700/420 = 1288/420
1288/420 simplified gives 46/15
So, 28/20 + 70/42 = 46/15
In mixed form: 31/15

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