AleksandrM wrote:Here is how I went about it:
First, conceptualize what you are told:
180x + 215y is < or = 2000
Then, just plug in answer choices.
You can eliminate all of the answer choices with odd numbers, because you cannot split a person in half (the problem tells you that HALF are 180 and the other HALF are 215).
So just pick B, and you see that it is 180(4) + 215(4) = 1580
So go on to the next choice, 180(5) + 215(5) = 1975, that's your answer.
Hope I am right![/u]
Great solution!
Instead of backsolving, we could have also solved algebraically.
Using your summation:
180x + 215y
and taking into account that x=y (since each group is half of the people),
we know that 395 is the weight of one person from each group. So, to find the answer, we can divide 2000 by 395 and then double our result to get the total number of people.
2000/400 would be 5, so 2000/395 will be 5 and a bit. Since we don't want bits of people in the elevator (that would be really bad for our shoes), we know that 5*2 = 10 will be the maximum number of people that we can fit inside: choose (D).
