Question

A cookie making company is trying to found out which of their cookies is the favorite among their 920 known customers. 80 customers are selected at random and asked which type of cookie they prefer, and this process is repeated 3 times. If 36 of the customers preferred mint cookies during the first sample, 33 preferred mint during the second sample, and 37 preferred them during the third, what is the most accurate estimate to how many of the company's customer's favorite cookie is mint?

a. About 414 of the customers
b. About 406 of the customers
c. About 380 of the customers
d. About 426 of the customers​

Answer 1

ANSWER :-

• Option B , About 406 of the customers.

GIVEN :-

• There are total 920 customers.
• 80 customers were selected randomly to take the test. 36 customers preferred mint during 1st sample , 33 customers preferred mint during 2nd sample and 37 customers preferred mint during 3rd sample.

TO FIND :-

• Number of customers whose favourite cookie is mint .

APPROACH :-

• We will find the average of all the samples , that is , 36 , 33 and 37. We will get the average customers whose favourite cookie is mint among 80 customers. Then we will solve furthur question by unitary method.

SOLUTION :-

Among 80 customers,

• 1st sample -- 36 customers
• 2nd sample -- 33 customers
• 3rd sample -- 37 customers

Average of 36 , 33 and 37 among 80 :-

Average customers = (36 + 33 + 37)/3

Average customers = 106/3

Average customers = 35.33

Hence , for every 80 customers , 35.33 customer's favourite cookie is mint.

____________________

For 80 customers → 35.33

For 920 customers → ?

We will apply unitary method ,

♦ For 1 customer → 35.33/80

♦ For 920 ,

ㅤㅤㅤㅤㅤ→ (35.33/80) × 920

ㅤㅤㅤㅤㅤ→ 0.44 × 90

ㅤㅤㅤㅤㅤ→ 406.3 customers

Hence , About 406 of 920 customers have favourite cookie as mint. Option B.

Answer 2

Option B is the correct answer