Answer
1.4 hours
Work Step by Step
We know the following equation for the velocity:
$\vec{v} \prime = v'cos(\theta) \hat{i} + v'sin(\theta)\hat{j}$
Adding in the wind, we find the x-component:
x: $v'cos\theta + V = 0 $
Solving this, we find:
$\theta=cos^{-1}(\frac{-V}{v'})=cos^{-1}(\frac{-190}{960}) =101^{\circ}$
We use the y component, which is $v=v'sin\theta$, to find:
$v = 960 sin(101^{\circ})=941 \ km/h$
Using the equation for change in time, we find:
$\Delta t = \frac{1290}{941}=1.4h$
