1.Three samples of five, five and five motor car tyres are drawn respectively from three brands A, B and C manufactured by three machines. The life - time of these tyres (in 1000 miles) is given below. Test whether the average life- time of the three brands of tyres are equal or not.

5. Three samples of five, five and five motor car tyres are drawn respectively from three brands A, B and C manufactured by three machines. The life - time of these tyres (in 1000 miles) is given below. Test whether the average life- time of the three brands of tyres are equal or not.

A B C

10 9 14

12 7 11

9 12 15

16 11 14

13 11 16