Question

350 people visited a zoo the zoo has four types of tickets the manager wants a sample of size 30, stratified by ticket type. how man teenagers should be in the sample *see attached*

Answer 1

Answer: 10

Explanation:

Given the following :

Total number of visitors = 350

Sample size = 30

Number selected from each strata is given by:

(Strata size ÷ Total population) × sample size

From the cumulative frequency distribution :

Child - 90

Teen - (210 - 90) = 120

Adult - (350 - 210) = 140

Senior = 0

Strata size of teen = 120

Therefore, number of teen selected is ;

(120 ÷ 350) × 30

0.3428571 * 30 = 10.26 (10 visitors)