To solve this problem, let us first assign some variables.
Let us say that:
v1 = velocity of airplane = 180 mph
t1 = time travelled by airplane
v2 = velocity of jet = 330 mph
t2 = time travelled by jet
Since we know that distance is the product of velocity and
time, and that the distance travelled by the two must be equal for the jet to
catch up to the plane, hence:
v1 * t1 = v2 * t2
But we know that:
t1 = t2 + 1
Therefore:
180 (t2 + 1) = 330 t2
180 t2 + 180 = 330 t2
150 t2 = 180
t2 = 1.2 hours
Therefore the jet can catch up to the plane after 1.2
hours it takes off.
