Answer:
p = 20
Step-by-step explanation:
Step1 :
Multiply each value by its frequency then add up :
(10 × 16) + (15 × 8) + (20 × p) + (25 × 10) + (30 × 6) = 20p + 610
Step2 :
Calculate the total of the frequencies :
6 + 8 + p + 10 + 6 = p + 30
The mean is equal to
[tex]\frac{20p+610}{p+30}[/tex]
Therefore
[tex]20.2 = \frac{20p+610}{p+30}[/tex]
then
20.2 × (p + 30) = 20p + 610
then
20.2p + 606 = 20p + 610
Then
20.2p - 20p = 610 - 606
Then
0.2p = 4
Then
p = 4/(0.2)
= 20
