A professional rock climber claims that he can climb a particular ...

[drink]

A professional rock climber claims that he can climb a particular mountain within half an hour. From a random sample of 20 attempts, the rock climber averaged 33.3 minutes with a standard deviation of 3.9 minutes.
 
  Is there sufficient evidence to suggest that the climber's claim is incorrect at a significance level of 10 per cent?

Question 2

What is the value of A?
 
  A) 6
  B) 5
  C) 3
  D) 2

[chreslie]

Answer to Question 1

H0 :   30 against H1 :  > 30
Test statistic t = (33.3 - 30 / (3.9/4.5 ) = 3.8
Since t19,0.1 = 1.328, we reject H0 at   0.1
Therefore, there is sufficient evidence to disprove the climber's claim.

Answer to Question 2

C

[drink]

Thanks for the timely response, appreciate it

[rachel]

Gracias!