The Pew Research Center asked a random sample of 2024adult cell-phone owners from the United States their age and which type of cell phone they own: iPhone, Android, or other (including non-smartphones). The two-way table summarizes the data.

Suppose we select one of the survey respondents at random.

a. Find P(iPhone|18-34).

b. Use your answer from part (a) to help determine if the events “iPhone” and "18-34"are independent.

Short Answer

Expert verified

Part a. 0.327

Part b. iPhone & 18-34are not independent.

Step by step solution

01

Part a. Step 1. Given information

The Table is-

02

Part a. Step 2. Calculation

We have,

P(iPhone|18-34)=169517=0.327

Therefore, the solution is0.327.

03

Part b. Step 1. Calculation

We have,

P(iPhone|18-34)=P(iPhone18-34)P(18-34)

If iPhone & 18-34are independent

=P(iPhone|·P(18-34)P(18-34)=P(iPhone)

Now,

P(iPhone)=4672024=0.23070.327

Therefore, iPhone & 18-34are not independent.

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