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cindyqtran
- Junior | Next Rank: 30 Posts
- Posts: 21
- Joined: Sun Aug 26, 2007 11:45 am
Just wanted to check if my logic is right, or I was just lucky.
7. A certain elevator has a safe weight limit of 2,000 pounds. What is the greatest possible number of people who can safely ride on the elevator at one time with the average (arithmetic mean) weight of half the riders being 180 pounds and the average weight of the others being 215 pounds?
(A) 7
(B) 8
(C) 9
(D) 10
(E) 11
----
This is how I solved it: 180 + 215 = 395
find avg of this: 395/2 = 197.5 (which is about 200)
2000/200 = 10
thanks!
7. A certain elevator has a safe weight limit of 2,000 pounds. What is the greatest possible number of people who can safely ride on the elevator at one time with the average (arithmetic mean) weight of half the riders being 180 pounds and the average weight of the others being 215 pounds?
(A) 7
(B) 8
(C) 9
(D) 10
(E) 11
----
This is how I solved it: 180 + 215 = 395
find avg of this: 395/2 = 197.5 (which is about 200)
2000/200 = 10
thanks!
