Mean = Sum of all the observations/ Number of observations = (87+46+90+78+89)/5 = 78
Variance = SD^2 ------ SD = Standard deviation
It means that with Variance, square root is never taken.
Therefore,
Variance = Summation of square of differences between observation and the mean divided by the number of observations.
That is,
Variance = {(87-78)^2 + (46-78)^2 + (90-78)^2 + (78-78)^2 + (89-78)^2}/5 = 274
Answer:
First choice: (1/4)(2 + v) = 3; v = 10 pounds of chopped vegetables
Step-by-step explanation:
"2 pounds of meat with some chopped vegetables"
2 + v
"She divides the mixture into 4 equal portions."
(1/4)(2 + v)
"Each portion weighs 3 pounds."
(1/4)(2 + v) = 3
2 + v = 12
v = 10
Answer: (1/4)(2 + v) = 3; v = 10 pounds of chopped vegetables
Answer:
6 knots
Step-by-step explanation:
Let the speed be v knots
then time taken to cover 500 M = 500 / v hrs
fuel consumption /hr = 216 + 0.5v^3
let F be the fuel consumption for trip
= [500/v][216 + 0.5v^3]
= 500[216/v + 0.5v^2]
dF/dv = 500[ - 216/v^2 + v]
d^2F/d^2v = 500[432/v^3 + 1] , i.e. +ve
so setting dF/dv will give a minima
500[ -216/v^2 + v] = 0
or v = 216/v^2
or v^3 = 216
solving, we get v = [216]^(1/3) = 6 knots
Answer:
9
Step-by-step explanation:
total is 30
spent is $9
this is total money minus the amount of the picture frame
30-9
21 divide by 3
the total sum of journals bought was 9