A car^s headlight produces an illumination of 9.6 foot candles at distance of 25 feet. What is the the illumination when the distance is 40 feet?

Question

I need help solving this word problem 

Answer 1

We are assuming an inverse variation: closer distance means higher light intensity and vice versa

9.6 = k /25

k = 9.6 * 25 = 240

I = 240/D where I is the intensity of the light in foot-candles and D is the distance

So then I = 240/40 = 6