If a 6, 7, or 8 shows up on a roll of a pair of dice, you win two dollars. If anything else shows up, you lose one dollar. If you roll the dice 300 times, what is your expected amount of winnings?
+2668 Note that there is a 49 chance to roll a 6,7, or 8.
This means that the remaining 59th of the time, you lose a dollar.
The expected value is the average of the outcomes, and it is: (2×49)+(−1×59)2=318
So, your expected amount of winnings is 318×300=50
