Answer: He will play 5 games in 9 hours .
Explanation:
In , he is playing 1 game
So, in 1 hour , he will play =
In 9 hours, he will play
Number of games can't be in decimals it must be in integers so we will take 5 only .
so he will play only 5 games in 9 hours .
The mean is and standard deviation is
. Then the variable
.
Use substitution , then the variable
.
The probability can be calculated in the following way:
for X=80, and
. From the diagram
.
Conclusion: if 188 students take the exam, then 188·0.84=157.92 (157) would receive a score above 80