The LCD for the two numbers is 10
10
A common denominator, though not the least, is 80.
10
10
60
60 is the least common denominator of 3 4 5 6 10 and 15.
5
100
100
It is 130
LCD(10, 11, 5) = 110.
The lowest common denominator would be 10, so 1/2 would be 5/10 and 1/5 would be 2/10.