Add 20/42 and 70/49, Solve 20/42 + 1 21/49 as a fraction

Add 20/42 and 70/49

1^st number: 20/42, 2^nd number: 1 21/49

20/42 + 70/49 is 40/21.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 49 is 294

Next, find the equivalent fraction of both fractional numbers with denominator 294
For the 1st fraction, since 42 × 7 = 294,
20/42 = 20 × 7/42 × 7 = 140/294
Likewise, for the 2nd fraction, since 49 × 6 = 294,
70/49 = 70 × 6/49 × 6 = 420/294
Add the two like fractions:
140/294 + 420/294 = 140 + 420/294 = 560/294
560/294 simplified gives 40/21
So, 20/42 + 70/49 = 40/21
In mixed form: 119/21

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