A is half good a work man as B and together they finish a job in 15 days. In how many days working alone B finish the job?
Choose the correct choice from the following choices:
A) 23
B) 22
C) 45 / 2
D) 36
E) 48

Rationale: "c 45 / 2 wc = 1 : 2 2 x + x = 1 / 15 = > x = 1 / 45 2 x = 2 / 45 = > 45 / 2 days"
Answer: C