The time it takes a truck to go a certain distance varies inversely with its rate of speed. If a certain trip takes 3 hours when the driver goes 30 mph, how long will the trip take when the driver goes 60 mph?
A) 1.7 hr
B) 1.4 hr
C) 1.5 hr
D) 1.6 hr
E) 1.3 hr

Question

Quizplus · Accepted Answer

The relationship between time and speed in this context is inversely proportional, meaning as one increases, the other decreases. The formula for this relationship is $T_1 \times S_1 = T_2 \times S_2$, where $T_1$ and $S_1$ are the original time and speed, and $T_2$ and $S_2$ are the new time and speed. Plugging in the given values: $3 \times 30 = T_2 \times 60$. Solving for $T_2$ gives $T_2 = 1.5$ hours.

The Time It Takes a Truck to Go a Certain