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

Add 70/42 and 28/70

1^st number: 1 28/42, 2^nd number: 28/70

70/42 + 28/70 is 31/15.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 70 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 42 × 5 = 210,
70/42 = 70 × 5/42 × 5 = 350/210
Likewise, for the 2nd fraction, since 70 × 3 = 210,
28/70 = 28 × 3/70 × 3 = 84/210
Add the two like fractions:
350/210 + 84/210 = 350 + 84/210 = 434/210
434/210 simplified gives 31/15
So, 70/42 + 28/70 = 31/15
In mixed form: 21/15

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