medea66 wrote:Forgot about combinations, thanks!
Hi Medea66,
Combinations is the simplest way to handle this problem. Here are my thoughts on how I would approach this problem.
1. The problem asked how many ways.. blah
So my first question is it a permutation or a combination ?
Here this is not an arrangement. Picking up bulb #3 and then bulb #4 is same as picking up bulb #4 and then picking up bulb #3.
Hence Combinations it the way to go.
2. I dint see any restrictions imposed. Hence is a simple combination problem.
The problem boils down to "in how many ways can I select 2 bulbs from a a box of 12".
soln is 12C2 = 66
This is a vanilla combinations problem in the low 500 range IMO. So u can expect this type of problem where u directly apply the formula.
HT Helps.