Mathematics (AS & A Level) · Oct / Nov 2018 · Paper 71 · Question 7

A mill owner claims that the mean mass of sacks of flour produced at his mill is 51 kg. A quality control officer suspects that the mean mass is actually less than 51 kg. In order to test the owner’s claim she finds the mass, x kg, of each of a random sample of 150 sacks and her results are summarised as follows. n = 150 Σx = 7480 Σx2 = 380 000

Read automatically from the paper; the printed page above is exact.