Trees in a certain park

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Trees in a certain park

by truplayer256 » Tue Aug 11, 2009 4:35 am
If 20% percent of the trees in a certain park are evergreen, and 40 % of the non evergreens are maple trees, and there are 75 % as many oak trees as maple trees in the park, what percent of the trees in the park are not maples,oaks or evergreens?

a) 10% b) 12 % C) 20 % d) 24% E) 25 %

I just wanted to confirm my answer to this question. My answer was D.

There are x trees in the park and:

.20(x)=Evergreen

.60(x)*.4=.32(x)=Maple

.75*.32(x)=.24(x)= Oak

x-.20(x)-.32(x)-.24(x)=x-.76(x)=.24(x)
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by mohitsharda » Tue Aug 11, 2009 5:49 am
Seems right to me.
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by georgeung » Tue Aug 11, 2009 7:57 am
I got the same thing.

Trees = 100

20%(100) = 20 Evergreens

80 trees left.
40%(100-20) = 32 Maple

75%(32) = 24 Oak

100-20-32-24= 24 other trees

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by gmatv09 » Tue Aug 11, 2009 11:36 am
Ans 24% (D)

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Re: Trees in a certain park

by way2kailash » Tue Aug 11, 2009 2:37 pm
truplayer256 wrote:If 20% percent of the trees in a certain park are evergreen, and 40 % of the non evergreens are maple trees, and there are 75 % as many oak trees as maple trees in the park, what percent of the trees in the park are not maples,oaks or evergreens?

a) 10% b) 12 % C) 20 % d) 24% E) 25 %

I just wanted to confirm my answer to this question. My answer was D.

There are x trees in the park and:

.20(x)=Evergreen

.60(x)*.4=.32(x)=Maple

.75*.32(x)=.24(x)= Oak

x-.20(x)-.32(x)-.24(x)=x-.76(x)=.24(x)
I think in the second equation you meant .80(x)*.4=.32(x) Maple

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by truplayer256 » Tue Aug 11, 2009 2:50 pm
I think in the second equation you meant .80(x)*.4=.32(x) Maple
No, .80(x)*4=3.2x not .32x.

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by way2kailash » Thu Sep 03, 2009 8:10 am
its 0.8*0.4, not 0.8*4
truplayer256 wrote:
I think in the second equation you meant .80(x)*.4=.32(x) Maple
No, .80(x)*4=3.2x not .32x.

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by Scott@TargetTestPrep » Thu May 09, 2019 4:54 pm
truplayer256 wrote:If 20% percent of the trees in a certain park are evergreen, and 40 % of the non evergreens are maple trees, and there are 75 % as many oak trees as maple trees in the park, what percent of the trees in the park are not maples,oaks or evergreens?

a) 10% b) 12 % C) 20 % d) 24% E) 25 %
We can let the number of trees = 100; thus:

20 are evergreen and so 80 are non-evergreen. Thus, 0.4 x 80 = 32 are maple.

The phrase "there are 75 percent as many oak trees as maple trees" means that the number of oaks is 75% of the number of maple trees. Thus, there are 3/4 x 32 = 24 oak trees.

So the percent that are not any of the above types is 100 - 20 - 32 - 24 = 24.

Answer: D

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