stats. ch9 pg235 Q48
plz find mean and mode
show steps plz and not formula only.
Answers
Step-by-step explanation:
Mid-value Frequency fx cf
5 15 75 15
15 20 300 35
25 25 625 60
35 24 840 84
45 12 540 96
55 31 1705 127
65 71 4615 198
75 52 3900 256
------ ---------
250 12600
(i) Mean:
= ∑fx/N
= 12600/250
= 50.4
(ii) Median:
N = 250, (N/2) = 125.
∴ l = 50, h = 10, f = 31, F = 96.
Median = l + (N/2 - F)/f * h
= [50 + (125 - 96)/31] * 10
= 1840/31
= 59.4
(iii) Mode:
Here, maximum frequency is 71, the corresponding class is 60-70 is modal class.
∴ l = 60, h = 10, f = 71, f₁ = 31, f₂ = 52.
Mode = [l + (f - f₁)/2f - f₁ - f₂] * h
= [60 + 40/59] * 10
= 3940/59
= 66.8
Hope it helps!