The position of a model train, in feet along the railroad track, is given by $s ( t ) = 3 t + 3$ after t seconds.
When will the train have moved a distance of 33 feet
A)after 30 seconds
B) after 10 seconds
C) after 13 seconds
D) after 12 seconds
E) after 11 seconds

Question

The position of a model train, in feet along the railroad track, is given by $s ( t ) = 3 t + 3$ after t seconds.  
When will the train have moved a distance of 33 feet  
A)after 30 seconds
B) after 10 seconds
C) after 13 seconds
D) after 12 seconds
E) after 11 seconds

Quizplus · Accepted Answer

To find when the train has moved 33 feet, set $s(t) = 33$:  $3t + 3 = 33$.  Solving for $t$, we get $3t = 30$, so $t = 10$ seconds.

The Position of a Model Train, in Feet Along the Railroad