Xr13-11 Every month a clothing store conducts an inventory and calculates losses from theft. The store would like to reduce these losses and is considering two methods. The first is to hire a security guard, and the second is to install cameras. To help decide which method to choose, the manager hired a security guard for 6 months. During the next 6-month period, the store installed cameras. The monthly n1 = 60, n2 = 45, s21

= 75, s22

= 10 n1 = 50, n2 = 50, s21

= 8, s22

= 14 n1 = 10, n2 = 16, s21

= 100, s22

= 15 n1 = 15, n2 = 15, s21

= 25, s22

= 15 x1 x1 = 409 x2 = 405 s2 = 54 n2 = 150 x1 = 412 s1 = 128 n1 = 150 losses were recorded and are listed here. The manager decided that because the cameras were cheaper than the guard, he would install the cameras unless there was enough evidence to infer that the guard was better. What should the manager do?

Security guard 355 284 401 398 477 254 Cameras 486 303 270 386 411 435