Suppose that the samples of polythene bags from two manufacturers A and B are treated by a prospective buyer for bursting pressure with the following results;

Bursting pressure (Ibs)	number of bags A B
5.0 - 9.9	2	9
10.0 - 14.9	9	11
15.0 - 19.9	29	18
20.0 -24.9	54	32
25.0 - 29.9	11	27
30.0 -34.9	5	13
	110	110

Required

Which set of bags has the highest average bursting pressure?

Which has more uniform pressure?

If prices are the same, which manufacturers bags would be preferred by the buyer and why?