An auto manufacturer has two plants that produce the same car. They are forced to close one of the plants. The company wants to know if theres a significant difference in production between the two plants. Daily production over the same 10 days is as follows:

Plant A Plant B

1184 1136

1203 1178

1219 1212

1238 1193

1243 1226

1204 1154

1269 1230

1256 1222

1156 1161

1248 1148

Which plant should be closed? And Why?