calculate the aritemetic mean,for the following frequency distribution

class interval frequency

0-80 22

80-160 35

160-240 44

240-320 25

320-400 24

class interval fi xi fixi 0-80 22 40 880 80-160 35 120 4200 160-240 44 200 8800 240-320 25 280 7000 320-400 24 360 8640 total 150 29520 mean= sigma fixi/fi =29520/150= 196.8