# I need help with a math problem

**Question description**

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.

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

2. The data below represents the number of hits on your web site over 10 months.

- Make a scatter plot of ln y versus x. Use the scatter plot to find the equation for the line of best fit.
- Make a scatter plot of ln y versus ln x. Use the scatter plot to find the equation for the line of best fit.
- Based on your answers in part a and b, would an exponential model or a power model be better to represent this data? Explain.
- Use your answers from parts a and b to find an exponential model and a power model to represent this data by hand.
- Use the regression feature on your calculator to find an exponential model and a power model to represent this data.
- Use your answer from parts c and d to make the best estimate for the number of hits your web site will have in 12 months.

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