Add 30/20 and 70/42, Solve 1 10/20 + 1 28/42 as a fraction

Add 30/20 and 70/42

1^st number: 1 10/20, 2^nd number: 1 28/42

30/20 + 70/42 is 19/6.

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,
30/20 = 30 × 21/20 × 21 = 630/420
Likewise, for the 2nd fraction, since 42 × 10 = 420,
70/42 = 70 × 10/42 × 10 = 700/420
Add the two like fractions:
630/420 + 700/420 = 630 + 700/420 = 1330/420
1330/420 simplified gives 19/6
So, 30/20 + 70/42 = 19/6
In mixed form: 31/6

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