The factors of 36 are listed and if you add the numbers together, the reason why he said he need more info was because there was more than on answer
1:1:36=38
18:2:1=21
9:2:2=13
4:3:3=10
12:3:1=16
6:6:1=13
9:4:1=14
6:3:2=11
She said her oldest played piano
6:6:1=13
9:2:2=13
there cant be two oldest so the answer is 9:2:2=13