Here's an example of a piecewise function that has three parts, where your choice of parts depends upon the input, x. If you order 57 shirts, you must use the "14x + 20" part of this function, because 57>50. Subst. 57 for x in "14x+20." You'll get 14*57 + 20, or $818.
What's the total cost of ordering 17 shirts? Note that 17 lies in the interval 0≤x<25. Therefore you use ONLY the "17x+20" part of the function:
17(17)+ 20 = $309.
32 shirts: 32 is in the second interval, so evaluate "15.80x+20." We get: 15.80(32)+20 = $525.60 (answer)
You plug the x value into whichever function it applies to. X represents the number of shirts ordered. So for example, the first question asks the total cost if you order 57 shirts. Look at the piecewise function. If says is x>50 (or equal), you use the equation 14x + 20. 57 is greater than 50 so plug it into the equation. (14)(57) + 20 = 818. You should be able to do the rest now. If you have any more questions, you can ask.
The probability that the value selected at random is greater than 30 will be found as follows: z-score is given by: z=(x-mu)/sig z=(30-30)/2=0 thus P(x>30)=1-P(X<30)=1-P(z<0)=1-0.5=0.5 Answer P(x>30)=0.5
