Question

please solve this question​

Answer 1

Answer:

Let assumed mean be A be 150

class class mark f d fd

xi xi-A

100-120 110 4 -40 -160

120-140 130 8 -20 -160

140-160 150 6 0 0

160-180 170 3 20 60

180-200 190 10 40 160

∑f = 31 ∑fd= -100

mean = A + ∑fd/∑f

=> 150 + [ (-100/31)]

=> 150 + (-3.22)

=> 150 - 3.22

=> 146.78