Add 28/15 and 21/42, Solve 1 13/15 + 21/42 as a fraction

Add 28/15 and 21/42

1^st number: 1 13/15, 2^nd number: 21/42

28/15 + 21/42 is 71/30.

Find the least common denominator or LCM of the two denominators:
LCM of 15 and 42 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 15 × 14 = 210,
28/15 = 28 × 14/15 × 14 = 392/210
Likewise, for the 2nd fraction, since 42 × 5 = 210,
21/42 = 21 × 5/42 × 5 = 105/210
Add the two like fractions:
392/210 + 105/210 = 392 + 105/210 = 497/210
497/210 simplified gives 71/30
So, 28/15 + 21/42 = 71/30
In mixed form: 211/30

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