Chapter 12: Q.AP4.8 - Cumulative AP Practise Test (page 828)

A large machine is filled with thousands of small pieces of candy, 40%of which are orange. When money is deposited, the machine dispenses60randomly selected pieces of candy. The machine will be recalibrated if a group of 60candies contains fewer than18that are orange. What is the approximate probability that this will happen if the machine is working correctly?

a. P(z<0.30.4(0.4)(0.6)60)Pz&1t;0.3-0.4(0.4)(0.6)60

b.P(z<0.30.4(0.3)(0.7)60)Pz&1t;0.3-0.4(0.3)(0.7)60

d. P(z<0.3-0.4(0.4)(0.6)60)Pz&lt;0.3-0.4(0.4)(0.6)60

c. P(z<0.3-0.4(0.4)(0.6)60)

Pz&lt;0.3-0.4(0.4)(0.6)60

e. P(z<0.4-0.3(0.3)(0.7)60)Pz&lt;0.4-0.3(0.3)(0.7)60

Short Answer

Expert verified

The approximate probability is

option (a)P(z<0.30.4(0.4)(0.6)60)Pz&1t;0.3-0.4(0.4)(0.6)60

Step by step solution

01

Given information 

Given in the question that, a large machine is filled with thousands of small pieces of candy, 40%of which are orange. When money is deposited, the machine dispenses 60randomly selected pieces of candy. The machine will be recalibrated if a group of 60 candies contains fewer than 18 that are orange. We need to find the approximate probability that will happen if the machine is working correctly .

02

Explanation

Thousands of small pieces of candy are stacked in a big machine, with orange candy accounting for 40%of the total. The issue here is population proportions. The issue is that 40%of the dollars are orange, indicating that the genuine population proportion is 0.4. For proportions, the z-score formula is:

z=p^-pp(1-p)n

=0.3-0.40.4(1-0.4)60

The answer is option (a).

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