Question

Tennis players often spin a racquet to decide who serves first. Th e spun racquet can land with the manufacturer’s label facing up or down. A reasonable question to investigate is whether a spun tennis racquet is equally likely to land with the label facing up or down. (If the spun racquet is equally likely to land with the label facing in either direction, we say that the spinning process is fair.) Suppose that you gather data by spinning your tennis racquet 100 times, each time recording whether it lands with the label facing up or down.

a. What are the observational units?

b. What is the variable?

Answer 1

a) The observational units in the study is the spinning of tennis racquet 100 times by a player.

Since we are the sample we have chosen is the spinning of tennis racquet by a player.

b) The variable in the study is number of times a tennis racquet land with the label facing up or down.

In this study we want to investigate whether a spun tennis racquet is equally likely to land with manufacturers label facing up or down.

If a spun is equally likely we would expect that approximately both the spun label facing up and down will occurs same number of time.