A bin of 5 transistors is known to contain 2 thatare defective. The transistors are to be tested, oneat a time, until the defective ones are identified.Denote by N1 the number of tests made until thefirst defective is identified and by N2 the number ofadditional tests until the second defective is identified.Find the joint probability mass function of N1and N2

Color Coding: Topics MINITAB Examples STT 351 Notes Normal −1 2 f x = 1 e 2 x ( ) 2Π inf < x < inf √ To find probabilities between two points (a,b] we have to integrate this function between a,b. Using MINITAB: 1) Calc 2) Probability distribution 3) Normal (mean = 0, Standard deviation = 1) 4) Select cumulative probability This will give the area under the curve up to the point x For any a value, the area under the curve up to the point a is = P(X ≤ a) # If we want to find the area under the curve between two points we can use the equation….. P( a < X ≤ b ) = P( X ≤ b ) – P( X ≤ a ) Using MINITAB: To find