A is the answer. it’s the answer
Answer:
x=9
Step-by-step explanation:
The given data is
Scores: 90-99 80-89 70-79 60-69 50-59
Students: 3 7 12 4 4
Because we are to take the middle value for each group.
Therefore the total score is
Sx = 3*94.5 + 7*84.5 + 12*74.5 + 4*64.5 + 4*54.5 = 2245
The number of students is 3+7+12+4+4 = 30
The mean is
m =2245/30 = 74.833
Calculate (Sx - m)²
(Sx - m)² = 3*(94.5-74.833)² + 7*(84.5-74.833)² + 12*(64.5-74.833)²
+ 4*(64.5-74.833)² + 4*(54.5-74.833)² = 3896.7
Calculate the standard deviation
s = √(3896.7/29) = 11.592
Answer:
mean = 74.83
std. deviation = 11.59
Answer:
The probabilities of the individual outcomes are the same.
The probability model for this situation is uniform.
Step-by-step explanation:
There is 2 of each number so there is an equal chance. when there is an equal chance that is uniform.
