Ask a New Question

the arithmetic mean of a set of nine numbers is 5. when one more number is added to the set, the new mean is 5.5. What number was added?

2 answers

I answered that already.
The total for 9 numbers is 45 and the total for 10 numbers is 55. Take the difference.

(9(5)+x)/10=5.5
45+x=55
x=10

Ask a New Question or answer this question.

Similar Questions

Three numbers are in the ratio 2:3:5. The first number, second number reduced by 5 and the third number form an arithmetic
1. 2 answers
if the arithmetic mean of four numbers is 20 and the arithmetic mean of other six numbers is 10 then,find the arithmetic mean of
1. 1 answer
three numbers in an arithmetic sequence sum up to six. if you add 1 to the first number, 2 to the second number, and 5 to the
1. 1 answer
The average (arithmetic mean) of 4 numbers is greater than 7 and less than 11. What is one possible number that could be the sum
1. 3 answers

more similar questions