Add 80/15 and 21/42, Solve 5 5/15 + 21/42 as a fraction

Add 80/15 and 21/42

1^st number: 5 5/15, 2^nd number: 21/42

80/15 + 21/42 is 35/6.

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,
80/15 = 80 × 14/15 × 14 = 1120/210
Likewise, for the 2nd fraction, since 42 × 5 = 210,
21/42 = 21 × 5/42 × 5 = 105/210
Add the two like fractions:
1120/210 + 105/210 = 1120 + 105/210 = 1225/210
1225/210 simplified gives 35/6
So, 80/15 + 21/42 = 35/6
In mixed form: 55/6

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