# Ti-83 Probability of events occurring

First time here, more frequent over at StackOverflow. So not sure if calculator questions are accepted here, but I'll ask.

Is there a quick way to solve problems like this in the ti-83:

1. 82% shot success rate out of 7 shots taken, find odds of exactly 3 shots going in, more than 5 shots going in. (I know how to do the written out way using nCr but it would save time on the exam if I knew a faster way).

2. Lets say 10% of people pay $\$$30, 70% pay \$$52, and 20% pay$\60. Is there a way to get the mean and standard deviation of that by modifying the stats on ti-83 (I know, very easy mean is (.1*30)+... just wondering if there a way without entering 30 1 time and 52 7 times and so on in L1 then calculating the 1 var stats.

Thanks!

• Figured out number 2 here: calculator.maconstate.edu/binomial_probability/index.html since I found out what its called. – NoviceCoding Mar 15 '11 at 4:36
• Just so you know, I fixed your formatting. The use of a dollar sign throws the text into math mode (as with LaTeX), and that messed up part of your question 2. – Mike Spivey Mar 15 '11 at 5:17
• Thanks man. Was wondering what was up with that. – NoviceCoding Mar 25 '11 at 19:03