Stats - Discrete Probability Distribution

[main osprey]

I have a Probability Distribution question, i've already attempted to solve it by getting the expected value of Winnings however I get -4.17 and the mark scheme for the question is confusing. if anyone can help that would be appreciated thank you.

[patent yoke]

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[astral loom]

the problem is poorly worded. It says that you pay 20 points to play the game, and you get those points back + some points only if you obtain an even score

for instance, if you play and obtain 1, then you lost 20 points

if you play and obtain 2, then you lost 20 points, that you get back, plus 2k points, so -20 + 20 + 2k = 2k points

[nimble prawn]

u saved his life

he was so excited showing me that u replied

and saved him

[main osprey]

Oh alr ty

[glacial willow]

@main osprey has given 1 rep to @astral loom

[main osprey]

+close