(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

An opaque bag contains 10 green counters, and 20 red ones. One counter is drawn at random and not replaced: green scores one, red scores zero. Five counters are drawn.

Find the probability of scoring 0, 1, 2, 3, 4, 5 points.

2. Relevant equations

3. The attempt at a solution

I found it pretty straighforward to work out with replacement, as it is just the simple binomial probability. But when the counters aren't replaced, surely the order counts, so i tried replacing nCr with nPr though this gave me the completely wrong answer. i know this resembles the lottery problem, but i don't understand what to do when there are only 2 distinguishable groups.

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Binomial probability, similar to lottery problems.

**Physics Forums | Science Articles, Homework Help, Discussion**