The sum of two numbers is 51 and the difference is 9. What are the numbers?
2 answers:
we dont know what is the two numbers so let us assume that one is x and other is y
so the sum of two numbers will be x+y which is equal to 51
and their difference is 9
so now we have two equations we can solve this by elimination method.
we know that we have -y and +y which is same value with opposite sign so we can cancel it and x+x will be 2x and 51+9=60
we can plug x=30 in any one of the equations
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Answer:
the game must be played in groups of 13 draws, with a cost of $28 for the 13 draws.
Step-by-step explanation:
Probability of drawing any of the 13 balls is the same. So the expected value of play is the average of the values of each card.
The only losing card is the ace; the player loses $20 if that card is drawn.
Each of the 3 face cards wins $10; each of the remaining 9 cards wins $2.
So the average value of each draw is
= 28/13
Therefore, on average the player will win $ 28/13. to be a fair game the player must pay $28/13 for a game.
that is not possible, unless the game must be played in groups of 13 draws, with a cost of $28 for the 13 draws.