Word Problem: Algebra?
To determine the number of deer in a game preserve, a conservationist catches 347 deer, tags them and lets them loose. Later, 468 deer are caught; 156 of them are tagged. How many deer are in the preserve?
Need to check my answer of 503
Comments
468 - 156 + 347 = 659
Or.... you could say that he caught 347 + 468 deer... which is 815 deer total... however becuase 156 have been tagged already, that means that they were already counted.... so because they were already counted, you subtract 156 from 815.
815 - 156 = 659
So, there are "AT LEAST" 659 deer in the preserve. Just because he caught 468 deer the 2nd time, there's no telling that he wouldn't catch something like, say, 739 on the 3rd catch attempt... in which case there will be some untagged deer waiting to be tagged.
I think you are a little* off... A lot of answerers are using basic math when algebra is called for (its not 659).
If 156 out of 468 caught are tagged, and there is a tagged population of 347 then your equation should read:
156/468 = 347/x (x being the total population of deer...
which reduces to
1/3 = 347/x
then, you can flip both sides(balancing)
3/1 or 3 = x/347
then
(3 * 347) = x
so, therefore
1041 = x
the total number of deer in the preserve would be 1041.
IM or email me if you need more explanation. Hope that helps.
It's not possible to determine how many there are from the information given. We only know that there are at least 659 deer in the preserve, (assuming that none of the tagged deer have died or escaped).
312 (468 -156 ) untagged
plus 347 previously tagged
Number of deers not tag = 468 - 156 = 312.
The number of deers in the preserve will 347(tagged deers) + 312 (untagged deers) = 659.
Note : This does not include deers which are not caught and not tag.
468 + 347 - 156 = 659
I agree with John N's answer and his method to calculate the answer using an algebraic formula.