Answer:
Variance = 4.68
Step-by-step explanation:
The formula for the variance is:
Where:
The mean can be calculated as each value multiplied by its probability
Replacing the mean and the summatory of X:
To answer this item, we have 4 as the speed of the kayaker in still water and the speed of current be y.
When the karayaker moves upstream or against the current, his speed would be 4 - y. Further, if he moves downstream or with the current, the total speed would be 4 + y. The time utilized for the travel is equal to the ratio of the distance and the speed.
Total time = 9/(4 - y) + 9/(4 + y) = 6
We multiply the equation by (4-y)(4+y)
9(4-y) + 9(4 + y) = 6(4-y)(4+y)
Simplifying,
72 = 96 - 6y²
Transposing all the constants to only one side of the equation and rearranging,
6y² = 96 - 72
y² = 4
y = 2
Hence, the speed of the river's current is 2 miles/hr. <em>The answer is letter B.) 2 miles/hour.</em>
Answer:
Some number or variable less than 5.
Step-by-step explanation:
Answer:
Step-by-step explanation:
Cost of a Road Trip Jesse's car gets 30 miles per gallon of gas. (a) If Las Vegas is 285 miles away, how many gallons of gas are needed to get there and then home? (b) If gas is $3.09 per gallon, what is the total cost of the gas for the trip.
