Questions about net gain. please help.?

Question

Story: A box has three red balls and five greens balls. A gambler bets $1 on red. A ball is randomly choosen. The gambler wins $1 if th ball is red, otherwise he loses $1. He will play this game 100 times.

Question: The expected value for the gambler's net gain is?

The SE for the gambler's net gain is?

The chance that the gambler will win between $0 and $5 is about?

a. 3.4%

b. 1%

c. 0.37%

d. 22%

e. 1.44%

Answer 1

SE?