Answer:
Option 3rd is the right choice.
Explanation:
Which of the following correctly describes the variation in the equation r=d/t?
Option 3rd is correct - r varies inversely with t and jointly with d
Inversely related means if the value of one entity increases, the value of second decreases and vice versa.
Here, r = d*1/t
So, we can say r = 1/t, this means r is in an inverse relation to t and direct relation to d.
So, option 3rd is the correct choice.