If it takes 6 hours for a plane to travel 720km with a tail wind and 8 hours to make the return trip with a head wind. Find the
1 answer:
Answer:
The air speed of the plane is 90 km/hr. and the wind has a speed of 15 km/hr.
Step-by-step explanation:
The plane travels 720 km in 6 hours in the direction of the wind and it takes 8 hours to make the round trip.
If we assume that the speed of the plane is u km/hr. and that of wind is v km/hr.
Therefore, we can write ........ (1)
And ..... (2)
If we add those two equations, then 2u = 210, ⇒ u = 105 km/hr.
Again from equation (2), we get v = u - 90 = 105 - 90 = 15 km/hr.
Therefore, the airspeed of the plane is 90 km/hr. and the wind has a speed of 15 km/hr. (Answer)
You might be interested in
Approx 60 feet see pic for work
The question is incomplete. The complete question is :
Let X be a random variable with probability mass function
P(X =1) =1/2, P(X=2)=1/3, P(X=5)=1/6
(a) Find a function g such that E[g(X)]=1/3 ln(2) + 1/6 ln(5). You answer should give at least the values g(k) for all possible values of k of X, but you can also specify g on a larger set if possible.
(b) Let t be some real number. Find a function g such that E[g(X)] =1/2 e^t + 2/3 e^(2t) + 5/6 e^(5t)
Solution :
Given :
a). We know :
So,
Therefore comparing both the sides,
Also,
b).
We known that
∴
Therefore on comparing, we get
∴