An apartment building has 25 floors with four apartments on each floor. The landlord wants to install new carpeting in twelve apartments to see how well the new carpet resists stains and tearing before he decides whether to replace the carpet in the entire building.
The following table shows the four apartments on each floor (identified A, B, C and D), as well as which apartments currently have children in residence (identified with “yes” in the appropriate cell). The landlord knows that carpeting typically experiences more stress in apartments with children.
|Floor||Unit A||Unit B||Unit C||Unit D|
Decide whether the following statements are true or false about this scenario.
In order to have an effective trial of the new carpeting, the landlord should select 12 of the 100 apartments completely at random to be the apartments which receive the new carpeting.
In order to have an effective trial of the new carpeting, the landlord should select 3 of the 25 floors completely at random, and then have all four apartments on each of those floors be the apartments which receive the new carpeting.
In order to have an effective trial of the new carpeting, the landlord should guarantee that two or three of the 12 apartments selected to receive new carpeting have children in residence.