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Recall the formula for combinations.
1/124 750
We are told that 500 boys, including Josh and Sokka, entered a drawing for two football game tickets. We are asked to find the probability that Josh and Sokka win the tickets. To do that, we will compare the number of favorable outcomes with the number of possible outcomes. P=Favorable outcomes/Possible outcomes Let's first calculate the number of possible outcomes of the drawing. Since each winner of the drawing gets the same ticket for a football game, the order of choosing the winners does not matter. Therefore, we will use combinations to calculate the number of possible outcomes.
Combinations |
The number of n distinct objects taken r at a time is denoted _nC_r and can be calculated using the following formula. _nC_r=n!/( n- r)! r! |
n= 500, r= 2
Subtract term
Write as a product
Cancel out common factors
Simplify quotient
Multiply
Calculate quotient