Question

A survey was conducted among 100 students of age groups 7−12 years and 13−18 years to find their favorite book genre. The students had to select any one genre out of detective, adventure, and biography. Out of the 50 students in the age group 7−12 years who participated in the survey, 23 liked adventure or biography. The total number of students of both age groups who liked detective books was 28.

Using a two-way table, compute the total number of students in the age group 13−18 years who liked adventure or biography.

23
27
49
51

Answer 1

The correct answer is C. 49.

Remember that there are 100 students divided into 7-12 and 13-18 age group. So there should be 50 for each. The table should go like this:

7-12 age group

23 adventure or biography

27 - detective

so you just have to subtract 50 from 23, which makes it 27. The remaining belongs to the 13-18 age group.

13-18 age group

1 - detective

49 - adventure or biography.

Answer 2

49

Explanation:

Total number of students =100

Out of the 50 students in the age group 7−12 years who participated in the survey, 23 liked adventure or biography.

So, 50-23 = 27 Out of the 50 students in the age group 7−12 years who participated in the survey liked detective

Now we are given that The total number of students of both age groups who liked detective books was 28.

No. of students of age group 13-17 who like detective books = Students of both age group like detective - No.of students of 7−12 years who liked detective = 28-27 =1

So ,The total number of students of both age groups who liked adventure or biography was 100-28 = 72

Since the age group 7−12 years who participated in the survey, 23 liked adventure or biography.

So, the age group 13-17 years who participated in the survey liked adventure or biography = 72-23=49

Age group Adventure or Biography Detective Total

7-12 23 27 50

13-18 49 1 50

Total 72 28 100

So, Option C is true.

The total number of students in the age group 13−18 years who liked adventure or biography. is 49