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If the zoo currently has 80 total birds, what is the smalles
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19 Jul 2019, 02:10
19 Jul 2019, 02:10
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34% (01:42) correct
65% (02:16) wrong based on 41 sessions
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#GREpracticequestion Approximately what percent of all the zoo’s animals.png [ 84.69 KiB | Viewed 5894 times ]
If the zoo currently has 80 total birds, what is the smallest number of birds that could be added such that at least 20% of the animals at the zoo would be birds?
(A) 10
(B) 80
(C) 100
(D) 125
(E) 200
Re: If the zoo currently has 80 total birds, what is the smalles
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25 Jul 2019, 18:53
25 Jul 2019, 18:53
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as 10% of birds=80, therefore, the total animals in the zoo ( 100%)=800.
Let's add X more birds to make the percentage of Birds AT LEAST 20 % of the total.
So, (80+x) is equal to or greater than 20% of ( 800+X)
80+x = 0.2(800+x)
80+x = 160+0.2x
-80= -0.8x
X=100
By calculation we get, X is greater than or equal to 100.
That is, if at least 100 birds are added, then we can get the desired percentage of bird population in the zoo.
Let's add X more birds to make the percentage of Birds AT LEAST 20 % of the total.
So, (80+x) is equal to or greater than 20% of ( 800+X)
80+x = 0.2(800+x)
80+x = 160+0.2x
-80= -0.8x
X=100
By calculation we get, X is greater than or equal to 100.
That is, if at least 100 birds are added, then we can get the desired percentage of bird population in the zoo.
Re: If the zoo currently has 80 total birds, what is the smalles
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18 Oct 2021, 05:44
18 Oct 2021, 05:44
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What would be the problem if we consider, There are a total of 100 birds. Thanks.
10+x = 0.2(100+x)
10+x = 20+0.2x
10= 0.8x
X=12.5
10+x = 0.2(100+x)
10+x = 20+0.2x
10= 0.8x
X=12.5
You cannot simply assume the total to be 100 as the question states that 10% of birds shown in the graph represents 80 birds from the total.
So if you would consider the total to be 100 then 10% of 100 doesn't equal to 80, so this contradicts with the question.
