please urgent help needed!!!!

Question

1. You randomly survey people in the mall about whether or not they regularly use text messaging. The results are shown in the tally sheets below based on the people’s ages.

1. Make a two-­way table that includes the marginal frequencies.
2. Make a two­-way table that shows both the joint and marginal relative frequencies. Round to the nearest hundredth, if necessary.
3. What is the probability that someone who is between the ages of 20-29 also texts regularly?
4. What is the probability that someone who is between the ages of 40-49 also texts regularly?
5. Does the data show a relationship between age and texting? Explain.

Answer 1

Hello Olivia,

I will show you part of the answer. See if you can work out the rest. (You may submit work and answers for an Expert to check.)

A two-way table of the basic data would look like this,

Age

20-29 30-39 40-49

Regularly 25 11 2

Texts

Not 7 13 10

Totals 32 24 12

You can also write another column with row totals on the right.

This chart can be used to find all sorts of probabilities. I will show you how to do number 3.

What is the probability that someone who is 20-29 texts regularly?

Since we are only interested in people 20-29 , I only look in the first column of the chart. There are a total of 32 people and 25 of them text so the answer is 25/32.

Look at your notes for the terminology used in 1 and 2 and see if you can do the rest of it.