E(X) = 1/7 + 2(1/7) + 3(1/7) + 4(1/7) + 5(1/7) + 6(1/7) + 7(1/7) = 1/7 + 2/7 + 3/7 + 4/7 + 5/7 + 6/7 + 7/7 = 24/7 = 4.
Var(X) = 1/7(1 - 4)^2 + 1/7(2 - 4)^2 + 1/7(3 - 4)^2 + 1/7(4 - 4)^2 + 1/7(5 - 4)^2 + 1/7(6 - 4)^2 + 1/7(7 - 4)^2 = 9(1/7) + 4(1/7) + 1/7 + 1/7 + 4(1/7) + 9(1/7) = 9/7 + 4/7 + 2/7 + 4/7 + 9/7 = 28/7 = 4
standard deviation = sqrt(Var(X)) = sqrt(4) = 2.
Answer:
1000
Step-by-step explanation:
Answer:
$5.71
Step-by-step explanation:
40 divided by 7 equals 5.71428571, which should be rounded to 5.71.