Probability of soft-drink machine

  • Thread starter superwolf
  • Start date
  • #1
176
0
A soft-drink machine discharges an average of 200 ml per cup, with a standard deviation of 15 ml. What is the probability that a cup contains between 191 and 209 ml?


Attempt:

[tex]Z_1 = \frac{190.5-200}{15} = -0.63[/tex]

[tex]Z_2 = \frac{209.5-200}{15} = 0.63[/tex]

The table in my book "Areas under the normal curve", gives P = 0.7357-0.2643 = 0.4714

Correct answer (according to the same book): 0.4514

Are my continuity corrections wrong?
 

Answers and Replies

  • #2
82
0
I don't think that you need a continuity correction here, unless the problem specifies that the machine can only dispense discrete amounts.

(209 - 200)/15 = .6

P(Z < .6) = .7257
.7257 - (1-.7257) = .4514
 

Related Threads on Probability of soft-drink machine

  • Last Post
Replies
6
Views
2K
  • Last Post
Replies
6
Views
787
Replies
6
Views
1K
  • Last Post
Replies
4
Views
252
  • Last Post
Replies
0
Views
1K
  • Last Post
Replies
0
Views
956
  • Last Post
Replies
1
Views
1K
  • Last Post
Replies
4
Views
2K
  • Last Post
Replies
1
Views
3K
Top