Calculation of The Ages of Three Daughters

How it was asked to find with some clues? 

The product of their age is 72; so possible combinations are,

3 x 3 x 8 = 72                       3 + 3 + 8 = 14

2 x 6 x 6 = 72                       2 + 6 + 6 = 14

2 x 2 x 18 = 72                     2 + 2 + 18 = 22

2 x 3 x 12 = 72                     2 + 3 + 12 = 17

2 x 4 x 9 = 72                       2 + 4 + 9 = 15

3 x 4 x 6 = 72                       3 + 4 + 6 = 13
 
If any of last 4 combinations was correct then I would have come to know ages of daughter straightaway as their sum is unique. So friend's house number as he must have told must be 14. That's why I was uncertain with the correct combination as they are appearing twice.

In next clue, he indirectly suggest he has only 1 oldest daughter. So 2,6,6 is eliminated as in that case he would have 2 oldest daughters.

So the correct combination is 3,3,8. That means he had oldest daughter of age 8 & younger twins.