SOLUTION: The average of a list of positive numbers is 20 per cent of the sum of the numbers. How many numbers are there in the list? (A) 5 (B) 20 (C) 80 (D) 100 (E) Cannot be sai

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Question 273631: The average of a list of positive numbers is 20 per cent of the sum of the
numbers. How many numbers are there in the list?
(A) 5 (B) 20 (C) 80 (D) 100 (E) Cannot be said.

Found 2 solutions by stanbon, richwmiller:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
The average of a list of positive numbers is 20 per cent of the sum of the
numbers. How many numbers are there in the list?
------------
Let the sum be "x":
---
Average = sum/#
---
Average = 0.20x
sum/# = 0.20x
x/# = 0.20x
# = 1/0.20
# = 5
==================
Cheers,
Stan H.





(A) 5 (B) 20 (C) 80 (D) 100 (E) Cannot be said.

Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
let s sum of list
let a= average
let n equal number of items in list
a=s/n
a=.2s=1/5*s
s/n=s/5
n=5