Question

Jonathan draws a ticket from a box to select the door prize winners at a party. The tickets are numbered from 1 to 25. What is the expected value that the tickets drawn will have numbers less than 5 if he draws tickets 40 tickets

Answer 1

Answer:

6

Step-by-step explanation:

Given that there are tickets in the draw which are numbered from 1 to 25.

Probability of an event E is given by the formula:

$P(E) = \dfrac{\text{Number of favorable cases}}{\text {Total number of cases}}$

Probability of each number can be found out as:

Number of favorable cases for each number is 1 and total number of cases here is equal to the total number of tickets i.e. 25.

$P(Each\ Number) = \dfrac{1}{25}$

Now, the numbers less than 5 mean 1, 2, 3 and 4.

Therefore, 4 number of favorable cases.

$P(1, 2, 3\ or\ 4) = \dfrac{4}{25}$

Now, it is given that 40 tickets are drawn.

Number of times, the numbers less than 5 are expected:

$\dfrac{4}{25}\times 40 \approx 6$