SOLUTION: from a deck of 10 cards that number 1-10, what are the chances of drawing 2 cards that equal 10. first you draw 1 card then put it back, shuffle and draw again.....

Algebra ->  Probability-and-statistics -> SOLUTION: from a deck of 10 cards that number 1-10, what are the chances of drawing 2 cards that equal 10. first you draw 1 card then put it back, shuffle and draw again.....      Log On


   



Question 299971: from a deck of 10 cards that number 1-10, what are the chances of drawing 2 cards that equal 10. first you draw 1 card then put it back, shuffle and draw again.....
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
There are 100 possible combinations of two card draws.
1 1
1 2
1 3
1 4
.
.
.
10 7
10 8
10 9
10 10
Only 9 of them sum to 10.
1+9=10
2+8=10
.
.
.
9+1=10
So the probability is 9/100.