Drawing Two Coins

Mar 2012
566
29
Define a sample space for the experiment of drawing two coins from a purse that contains two quarters, three nickels, one dime, and four pennies.

Q - Quarter
N - Nickel
D - Dime
P - Penny

S = {QQ, QN, QP, QD, DN, DP, NP, NN, PP}
This is the book answer.

I am wondering why the sample space did not include NQ, PQ, DQ, ND, PD, PN?
 

romsek

MHF Helper
Nov 2013
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The experiment doesn't care about the order of the drawings, only the result after drawing two.

NQ is included as QN, PQ as QP, etc.
 
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Mar 2012
566
29
How do we know that the experiment doesn't care about the order of the drawings?
 

romsek

MHF Helper
Nov 2013
6,746
3,037
California
How do we know that the experiment doesn't care about the order of the drawings?
generally if order matters they'll say so.

In this problem you can infer order doesn't matter because you are drawing "two coins", not one after the other.
 
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