Question

A game of chance consists of spinning an arrow on a circular board, divided into 8 equal parts, which comes to res pointing at one of the numbers 1, 2, 3,...., 8 (Fig. 9), which are equally likely outcomes. What is the probability that the arrow will point at (i) an odd number (ii) a number greater than 3 (iii) a number less than 9.

Answer 1

Answer:

(i) $\frac{1}{2}$

(ii) $\frac{5}{8}$

(iii) 1

Step-by-step explanation:

Size of sample space = 8

(i) Number of odd numbers = 4

Therefore, probability of an odd number = $\frac{4}{8}$

or,   $\frac{1}{2}$

(ii) Number of number greater than 3 = 5

Therefore, probability of a number greater than 3= $\frac{5}{8}$

(iii) Number of numbers less than 9 = 8

Therefore, probability of a number lesser than 9= $\frac{8}{8} = 1$

Answer 2

Answer:

(i) 1/2 (ii) 5/8 (iii) 1

Step-by-step explanation:

(1) An odd number:

There are 8 numbers altogether

There are 4 odd numbers (They are 1, 3, 5 and 7)

P(odd number = 4/8 = 1/2

(2) A number greater than 3

There are 8 numbers altogether

There are 5 numbers greater than 3 (They are 4, 5, 6, 7 and 8)

P(greater than 3) = 5/8

(3) A number less than 9

There are 8 numbers altogether

There are 8 numbers less than 9

P(Less than 9) = 8/8 = 1

Answer: (i) 1/2 (ii) 5/8 (iii) 1