Statistics
posted by Mitch on .
Suppose that 92% of all SFSU students own a cell phone. Find the probability that 7 out of 10 random selected SFSU students own a cell phone.
explain how answer was arrived

P(7) = (0.92)^7*(0.08)^3*[10!/(7!*3!)]
= (10*9*8)/(1*2*3)]*(0.92)^7*(0.08)^3
= 0.03427
P(10)= 0.92^10 = 0.43439
P(9) = 0.92^9*0.08*10 = 0.37777
P(8) = 0.92^8*0.08^2*(10*9/2)=0.14781