mean of 10 number is 50 if one number is added is the mean is itself 50 find the added - Maths - Statistics

Question

mean of 10 number is 50 if one number is added is the mean is
itself 50 find the added number

Varun.Rawat · Accepted Answer

Let x1, x2, x3, 
,x10 be the 10 observations
Mean of 10 observations = x1 + x2 + x3 + 
+x1010⇒50 = x1 + x2 + x3 + 
+x1010⇒x1 + x2 + x3 + 
+x10 = 500Let the added number be x11
Number of observations = 11Now, mean = 50⇒x1 + x2 + x3 + 
+x10 + x1111 = 50⇒x1 + x2 + x3 + 
+x10 + x11 = 550⇒500 + x11 = 550⇒x11 = 550 - 500 = 50So, added number = 50

mean of 10 number is 50 if one number is added is the mean is itself 50 find the added number