Shoes Boy and Whistle Puzzle

Shoes + Shoes + Shoes = 30
Shoes + Boy + Boy = 20
Boy + Whistle + Whistle = 13
Shoes + Boy x Whistle = ?
What is the Value of "?" and of Shoes, Boy and Whistle ?
Look Closely for the right Values.
Click here for Answer
Logic :Value of Shoe = 10
Value of man with whistle = 5
Value of 1 pair of Whistle = 4
So,
Value of man without Whistle : 3
Hence answer = 10 + (3*2) = 16 ( by BODMAS rule)
Answer is 16.