Question

The probability of occurence of an event is 9/10.What is the probabilty that an event will occur at least 4 times put of 5

Answer 1

Answer:

Please see the attachment

Answer 2

Concept

The probability of getting success must remain same for each trials we are investigating.

Given

Probability of occurence of an event is 9/10

Find

The probability of an event which will occur at least 4 times out of 5.

Solution

We are given that

P(success) = p = 9/10

P(Failure) = q = 1 - 9/10 = 1/10

n = 5

x = 4

Using Formula

P(x=4) = ⁿCₓ pˣ qⁿ⁻ˣ

P(x=4) = ⁵C₄ (9/10)⁴(1/10)¹

P(x=4) = 5(9⁴ /10⁵)

P(x=4) = (5 * 9 * 9 * 9 * 9)/100000

P(x=4) = 32805/100000

The probabilty that an event will occur at least 4 times put of 5 is 32805/100000.

#SPJ2