Question

The mean of 20 students is 155 cm it was later discovered later on that while calculating the reading 149 was wrongly read as 189 find the correct mean height

Answer 1

Answer:

153

Step-by-step explanation:

Concept;

$Mean=\frac{sum\:of\:observations}{Number\;of\:observations}$

That is,

Mean = (∑x)/n

Given:

n=20

Mean = 155

(∑x)/n = 155

(∑x)/20 = 155

∑x = (155)(20)

∑x = 3100

corrected ∑x = 3100-189+149

corrected ∑x = 3100-40

corrected ∑x = 3060

correct mean

=(corrected ∑x)/n

=3060/20

=306/2

=153