An epidemic is reported to have broken out in Florida. The number of detected instances of a certain disease is reported to have increased by 85% in the last year. What is the lowest number of newly detected instances possible?
(A) 1
(B) 5
(C) 11
(D) 15
(E) 17
OA E
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GMATGuruNY
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Let x = the OLD number of instances.guerrero wrote:An epidemic is reported to have broken out in Florida. The number of detected instances of a certain disease is reported to have increased by 85% in the last year. What is the lowest number of newly detected instances possible?
(A) 1
(B) 5
(C) 11
(D) 15
(E) 17
OA E
Since the number of instances increases by 85%, the number of NEW instances = (85/100)x = (17/20)x.
Since the number of new instances must be an integer, the minimum value of x = 20.
Thus, the minimum number of NEW instances = (17/20)20 = 17.
The correct answer is E.
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ranjeet75
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[quote="GMATGuruNY"][quote="guerrero"]An epidemic is reported to have broken out in Florida. The number of detected instances of a certain disease is reported to have increased by 85% in the last year. What is the lowest number of newly detected instances possible?
(A) 1
(B) 5
(C) 11
(D) 15
(E) 17
OA [spoiler]E[/spoiler][/quote]
Let x = the OLD number of instances.
Since the number of instances increases by 85%, the number of NEW instances = (85/100)x = (17/20)x.
Since the number of new instances must be an integer, the minimum value of x = 20.
Thus, the minimum number of NEW instances = (17/20)20 = 17.
The correct answer is [spoiler]E[/spoiler].[/quote]
If x = old no. of instances and the instances increased by 85%,
so, no. of new instances = (185/100)*x
Where am I wrong? Please clarify.[/b]
(A) 1
(B) 5
(C) 11
(D) 15
(E) 17
OA [spoiler]E[/spoiler][/quote]
Let x = the OLD number of instances.
Since the number of instances increases by 85%, the number of NEW instances = (85/100)x = (17/20)x.
Since the number of new instances must be an integer, the minimum value of x = 20.
Thus, the minimum number of NEW instances = (17/20)20 = 17.
The correct answer is [spoiler]E[/spoiler].[/quote]
If x = old no. of instances and the instances increased by 85%,
so, no. of new instances = (185/100)*x
Where am I wrong? Please clarify.[/b]
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sidceg
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Percentage increase means [(New - Old)/Old]*100ranjeet75 wrote:If x = old no. of instances and the instances increased by 85%,GMATGuruNY wrote:Let x = the OLD number of instances.guerrero wrote:An epidemic is reported to have broken out in Florida. The number of detected instances of a certain disease is reported to have increased by 85% in the last year. What is the lowest number of newly detected instances possible?
(A) 1
(B) 5
(C) 11
(D) 15
(E) 17
OA E
Since the number of instances increases by 85%, the number of NEW instances = (85/100)x = (17/20)x.
Since the number of new instances must be an integer, the minimum value of x = 20.
Thus, the minimum number of NEW instances = (17/20)20 = 17.
The correct answer is E.
so, no. of new instances = (185/100)*x
Where am I wrong? Please clarify.[/b]
Hence it should be [(185-100)/100]*x and not (185/100)*x.
