Question

Sammy is playing a board game. He rolls two number cubes, each numbered 1-6. If he rolls a sum of 2 he wins $50; otherwise he loses $5. How much should Sammy expect to win or lose on average per roll?

Answer 1

he is supposed to lose an average of 1.36$ per roll

Answer 2

Sammy loses $3.47 on average

Explanation:

When you roll two number cubes, the number of possible combinations is 36 ( 6 * 6 ).

The only way to get a sum of two is rolling snake eyes (two ones), which means there's only one combination that gets this sum.

The chances of winning is 1/36 whilst the chance of losing is 35/36

$50*(1/36) - $5(35/36) = $1.39 - $4.86 = -$3.47

which means Sammy loses $3.47 on average