Solution:
Given the mean of 20 numbers = 18
Sum of numbers = 18×20 = 360
If 3 is added to each of first 10 numbers, then new sum = (3×10)+360
= 30+360
= 390
New mean = 390/20
= 19.5
Hence the mean of new set of 20 numbers is 19.5.
The mean of 20 numbers is 18. If 3 is added to each of the first ten numbers, find the mean of new set of 20 numbers.
The mean of 20 numbers is 18. If 3 is added to each of the first ten numbers, find the mean of new set of 20 numbers.