please help i need help on question b
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There are 12 possible outcomes.....three of these will be a "7" ...so...
A "7" should occur 1/4 of the time
If each player pays 20p to play.....the school will take in 120 * 20 = 2400p
However.......1/4 of the players should win = 30 players.....and each lollipop costs 30p.....so......the school should spend 30 * 30 = 900p for the prizes
So......the school should raise 2400 - 900 = 1500p if 120 people play the game
Answer:
1500p or $15
Step-by-step explanation:
School either earns 20,
or loses 10 (20 - 30 = -10)
P(-10) = P(score is 7) = 3/12 = 1/4
P(20) = P(not a 7) = 1 - 1/4 = 3/4
Expected gain each game:
(-10)(1/4) + (20)(3/4)
12.5
If 120 games:
120 × 12.5
1500p
$15