A media report claims that 50% of U.S. teens with smartphones feel addicted to their devices.3 A skeptical researcher believes that this figure is too high. She decides to test the claim by taking a random sample of 100 U.S. teens who have smartphones. Only 40 of the teens in the sample feel addicted to their devices. Does this result give convincing evidence that the media report’s 50% claim is too high? To find out, we want to perform a simulation to estimate the probability of getting 40 or fewer teens who feel addicted to their devices in a random sample of size 100 from a very large population of teens with smartphones in which 50% feel addicted to their devices.

Let 1 = feels addicted and 2 = doesn’t feel addicted. Use a random number generator to produce 100 random integers from 1 to 2. Record the number of 1’s in the simulated random sample. Repeat this process many, many times. Find the percent of trials on which the number of 1’s was 40 or less.

Determine whether the simulation design is valid. Justify your answer.