In a survey on three products, A, B, and C, 50% of those

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In a survey on three products, A, B, and C, 50% of those surveyed liked product A, 30% liked product B, 20% liked product C, and 85% liked at least one of the three products. If 5% of those surveyed like all three products, then what percentage of those surveyed liked more than one of the products?

A. 5
B. 10
C. 15
D. 20
E. 25

The OA is B

Source: Veritas Prep
Source: — Problem Solving |

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by Jay@ManhattanReview » Sun Nov 03, 2019 11:48 pm
swerve wrote:In a survey on three products, A, B, and C, 50% of those surveyed liked product A, 30% liked product B, 20% liked product C, and 85% liked at least one of the three products. If 5% of those surveyed like all three products, then what percentage of those surveyed liked more than one of the products?

A. 5
B. 10
C. 15
D. 20
E. 25

The OA is B

Source: Veritas Prep
So we have

Percentage of surveyors who liked the products A, B, or C = 50%; it includes two products, and three products as well

Percentage of surveyors who liked the product A = A = 50%; it may include who liked B and C as well.
Percentage of surveyors who liked the product B = B = 30%; it may include who liked A and C as well.
Percentage of surveyors who liked the product C = C = 20%; it may include who liked B and A as well.

Say,

Percentage of surveyors who liked both products A and B, but not C = AB;
Percentage of surveyors who liked both products A and C, but not B = AC;
Percentage of surveyors who liked both products B and C, but not A = BC; and
Percentage of surveyors who liked all three products A, B and C = ABC = 5%

Thus, we have

85 = A + B + C - AB - AC - BC - 2*ABC

85 = 50 + 30 + 20 - (AB + AC + BC + 2*ABC)

85 = 100 - (AB + AC + BC + 2*5)

=> AB + AC + BC = 100 - 85 - 10 = 5%

=> those surveyed liked more than one of the products = AB + AC + BC + ABC = 5% + 5% = 10%

The correct answer: B

Hope this helps!

-Jay
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by [email protected] » Mon Nov 04, 2019 9:20 am
Hi swerve,

We're told that in a consumer survey, 85% of those surveyed liked at least one of three products: A, B, and C. 50% of those asked liked product A, 30% liked product B, 20% liked product C and 5% of the people in the survey liked ALL THREE products. We're asked for the percentage of the survey participants who liked MORE than ONE of the three products.

A three-group Overlapping Sets question can be solved in a coupe of ways: with a 3-circle Venn Diagram or with a Formula. Here, we have to also account for those who like NONE of the groups; that would be 100% - 85% = 15% of those surveyed.

Total = (Those who like NONE) + (Gp. A) + (Gp. B) + (Gp. C) - (Gp A&B) - (GpA&C) - (GpB&C) - 2(All 3)

With the data in the prompt, we can fill in most of the formula:

Total = (None) + (Gp. A) + (Gp. B) + (Gp. C) - (Gp A&B) - (GpA&C) - (GpB&C) - 2(All 3)
100% = (15%) + (50%) + (30%) +(20%) - (Gp A&B) - (GpA&C) - (GpB&C) - 2(5%)
100% = 115% - (Gp A&B) - (GpA&C) - (GpB&C) - 10%
(Gp A&B) - (GpA&C) - (GpB&C) = 5%

We now know that 5% of those surveyed liked EXACTLY 2 of the products. The question asks for the percentage of people who liked MORE than 1 product, so that includes those who like exactly 2 and those who like ALL 3:

5% + 5% = 10%

Final Answer: B

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Rich
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by Scott@TargetTestPrep » Wed Nov 06, 2019 7:12 pm
swerve wrote:In a survey on three products, A, B, and C, 50% of those surveyed liked product A, 30% liked product B, 20% liked product C, and 85% liked at least one of the three products. If 5% of those surveyed like all three products, then what percentage of those surveyed liked more than one of the products?

A. 5
B. 10
C. 15
D. 20
E. 25

The OA is B

Source: Veritas Prep
The problem really asks for the percentage of people who liked 2 or 3 products.

We can create the following equation:

Total percentage of people = percentage who like product A + percentage who like product B + percentage who like product C - (percentage who like 2 products) - 2(percentage who like 3 products) + percentage who like none of the products

Let's represent the percentage who like 2 products as D and the percentage who like none of the products as N. Then:

100 = 50 + 30 + 20 - D - 2(5) + N

100 = 90 - D + N

We are also given that 85% of the people surveyed liked at least one of the three products. Thus, 100 - 85 = 15 percent of the people liked none of the three products. So we have:

100 = 90 - D + 15

D = 5

Thus, 5 + 5 = 10 percent of the people like more than one product.

Answer: B

Scott Woodbury-Stewart
Founder and CEO
[email protected]

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