Table A.2: Service time on the cashier of χ2 test statistics.

i x
(seconds)
fi pi npi (fi-npi)
1 0-40 43 0.501 47.634 -4.634 0.451
2 40-80 28 0.250 23.750 4.250 0.761
3 80-120 14 0.125 11.841 2.159 0.393
4 120-160 7 0.062 5.904 1.096 0.203
5 160 above 3 0.062 5.871 -2.871 1.404
Total 95 1.000 95.000 0.000 3.212

Note: i is each interval; x is the arrival number per second.