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Bunuel
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In a recent scientific study, patients with colds were separated into 06 Jul 2022, 01:30
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95% (hard)

Question Stats:

43% (02:49) correct 57% (02:54) wrong based on 149 sessions

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In a recent scientific study, patients with colds were separated into 2 groups and treated with one of two antibiotics, A or B. Twenty-five percent of those that were treated with antibiotic A were in group 1 and 43% of the patients were in group 1. If 72% of patients received antibiotic B, which of the following is closest to the percent of patients in group 2 that received antibiotic B?

A. 21%
B. 28%
C. 36%
D. 50%
E. 63%


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E
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In a recent scientific study, patients with colds were separated into 06 Jul 2022, 02:24
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We need to set up a double matrix, which is hard to reproduce in text form.

The key fact is: 43% are in group 1. 57% are in group 2. 28% are treated by A. 72% are treated by B.
21% are in group 2 and are treated by A.
36% are in group 2 and are treated by B.

So, the answer is
36/57, which is approximately 63%.
The answer is thus (E).
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In a recent scientific study, patients with colds were separated into 06 Jul 2022, 19:21
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Bunuel
In a recent scientific study, patients with colds were separated into 2 groups and treated with one of two antibiotics, A or B. Twenty-five percent of those that were treated with antibiotic A were in group 1 and 43% of the patients were in group 1. If 72% of patients received antibiotic B, which of the following is closest to the percent of patients in group 2 that received antibiotic B?

A. 21%
B. 28%
C. 36%
D. 50%
E. 63%



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Using the double matrix method,­
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File comment: There are 54% people who received antibiotic B in group 2. Answer is (D) IMO.
Untitled.png
Untitled.png [ 5.92 KiB | Viewed 3238 times ]

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In a recent scientific study, patients with colds were separated into 06 Jul 2022, 22:37
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Bunuel
In a recent scientific study, patients with colds were separated into 2 groups and treated with one of two antibiotics, A or B. Twenty-five percent of those that were treated with antibiotic A were in group 1 and 43% of the patients were in group 1. If 72% of patients received antibiotic B, which of the following is closest to the percent of patients in group 2 that received antibiotic B?

A. 21%
B. 28%
C. 36%
D. 50%
E. 63%
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Create a distribution table as below

Attachment:
File comment: Table of distribution
Distribution.jpeg
Distribution.jpeg [ 25.42 KiB | Viewed 3103 times ]

The percentage of patients in group 2 that received antibiotic B = \(36/57 = 12/19 > 12/20 = 60%\)

Hence, the answer is E.
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In a recent scientific study, patients with colds were separated into 25 Jul 2022, 20:14
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Bunuel
In a recent scientific study, patients with colds were separated into 2 groups and treated with one of two antibiotics, A or B. Twenty-five percent of those that were treated with antibiotic A were in group 1 and 43% of the patients were in group 1. If 72% of patients received antibiotic B, which of the following is closest to the percent of patients in group 2 that received antibiotic B?

A. 21%
B. 28%
C. 36%
D. 50%
E. 63%

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twoface07, it looks like you've got a 25 where it should be 25% of those who were treated with antibiotic A, so that 25 should be a 7 (25% of 28).

36/57 is more than 50%.

Answer choice E.
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In a recent scientific study, patients with colds were separated into 04 Aug 2025, 22:53
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How is the answer E?
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In a recent scientific study, patients with colds were separated into 06 Aug 2025, 06:04
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Shrutiv134
How is the answer E?
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Request you to kindly specify your doubt post going through above solutions, or share your working on the problem - that would help others to address your doubt effectively.
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