13 6 2 =20 4 9 5=11 then 15 5 4 puzzle answer

Answer: 55

Solution:

#Puzzle_answer:

13 x 2 - 6= 26-6= 20,
5 x 4 - 9= 20-9= 11,
9 x 3 - 2= 27-2= 25,
And finally
15x4 - 5= 60-5= 55

Cheers !!!