Video Transcript
Chloe is designing a simulation to model the ice cream sales at a local cafe. Last week, 70 percent of the ice cream sold were chocolate, 20 percent were vanilla, and 10 percent were strawberry. She’s going to use a spinner to generate data to predict this week’s sales. Which spinner should she use?
We’re given four different spinners, each with the section labeled A, B, and C. We know that 70 percent of the ice cream sold were chocolate, 20 percent were vanilla, and 10 percent were strawberry. If we’re going to use a spinner, we have to remember the number of degrees in a full turn. One full turn is 360 degrees.
If chocolate sales were 70 percent of the total, then the chocolate portion of the spinner can be found by multiplying 70 percent by 360. We need to find 70 percent of 360. To multiply 70 percent, we write 70 percent in its decimal form, 0.70, and then we multiply 0.70 by 360. When we do that, we get 252 degrees. Which tells us that the chocolate portion of the spinner should measure 252 degrees.
Vanilla sales were 20 percent. The first thing we can do is write 20 percent as a decimal, 0.20, and then multiply that by 360 degrees. Which gives us 72 degrees. The vanilla portion of our spinner should be 72 degrees.
Strawberry sales were 10 percent of total sales. We could multiply 10 percent by 360. However, if we recognize that 10 percent is half of 20 percent, 20 percent divided by two. Then, we can divide the degrees for the vanilla sales, which was the 20 percent. We can take 72 degrees and divide that by two, which gives us 36 degrees. 10 percent written as a decimal, 0.10, multiplied by 360 is equal to 36 degrees. The strawberry portion of the spinner should then be 36 degrees.
Our spinner should have one section measuring 252 degrees, one section measuring 72 degrees, and a final section measuring 36 degrees. The first spinner is the only spinner that meets these requirements.
Chloe will perform 50 trials. Describe what a single trial will entail.
We know that the trial will include a use of the spinner we found in the first part of the problem. So, we can say that a trial consists of spinning the spinner once. And after the spinner is spun, one of three things will happen. The spinner could land on A, the blue section, which would represent a customer choosing chocolate. It could land on B, the yellow section, which represents a customer choosing vanilla. Or finally, it could land on C, the green section, which represents a customer choosing strawberry.
