The distance (d) a moving body travels, varies directly with the time (t) when it moves. A train travels 72 km in 2 hours. Find the equation that relates d and t.
Show answer & explanation
Correct answer: D
Explanation
The correct answer is Option 4 i.e. d = 36t.
Since distance d varies directly with time t, we can write this relationship as:
d = k × t
where k is the constant of proportionality
Now,
⇒ 72 = k × 2
⇒ k = 72/2
⇒ k = 36
Thus, the equation relating d and t is:
⇒ d = 36t