find a new mean if 2,4 is added and 5 is subtracted from data of mean 20 and terms 100

Asked by tapiawalabipin | 9th Jan, 2020, 08:43: AM

Expert Answer:

Given: Mean = 20
Number of observations = 100
To find the new mean if 2, 4 is added and 5 is subtracted from each of the observations.
x with bar on top equals 20
rightwards double arrow begin inline style sum from i equals 1 to 100 of end style space x subscript l equals 20 cross times 100 equals 2000
N e w space s u m equals open parentheses x subscript 1 plus 2 plus 4 minus 5 close parentheses plus open parentheses x subscript 2 plus 2 plus 4 minus 5 close parentheses plus... plus open parentheses x subscript 100 plus 2 plus 4 minus 5 close parentheses
equals open parentheses x subscript 1 plus 1 close parentheses plus open parentheses x subscript 2 plus 1 close parentheses plus... plus open parentheses x subscript 100 plus 1 close parentheses
equals x subscript 1 plus x subscript 2 plus... plus x subscript 100 plus 100 equals begin inline style sum from i equals 1 to 100 of end style begin inline style space end style begin inline style x subscript l end style begin inline style plus end style begin inline style 100 end style begin inline style equals end style begin inline style 2100 end style begin inline style space end style begin inline style rightwards double arrow end style begin inline style N end style begin inline style e end style begin inline style w end style begin inline style open parentheses x with bar on top close parentheses end style begin inline style equals end style fraction numerator N e w open parentheses sum from i equals 1 to 100 of space x subscript l close parentheses over denominator 100 end fraction begin inline style equals end style 2100 over 100 begin inline style equals end style begin inline style 21 end style

Answered by Renu Varma | 9th Jan, 2020, 10:46: AM