Question

You need to borrow money for gas, so you ask your mother and your sister. You can only borrow money from one of them. Before giving you money, they each say they will make you play a game. Your sister says she wants you to flip a fair coin. She will give you $9 for heads and $21 for tails. Your mother says she wants you to roll a six-sided die. She will give you $5 times the number that appears on the die. Determine the expected value of each game and decide which offer you should take.

Answer 1

$30 for the flip a coin game.
$105 for the dice game.
- > heads = $9
-> tails = $21
^ $9+$21=$30

dice game-
6 sides of a dice, she doubles it by 5.
1*5 + 2*5 + 3*5 + 4*5 + 5*5 + 6*5
^ 5+10+15+20+25+30= 105.
-> $105 for dice game.

you can easily get $9/$21 from your sister, but it won’t be as much from the dice, but you have more risk going with the dice since there’s 6 sides. the highest to get from your mother is $30 and the highest from your sister is $21, but the dice is the better deal.