Taxi charges in a city consist of fixed charges and the remaining depending upon the distance travelled in kilometres. If a man travels 80 km, he pays Rs. 1330, and travelling 90 km, he pays Rs.1490. Find the fixed charges and rate per km.

Let the fixed charge of taxi be x.

Excluding fixed charge, a man pays Rs. (1330 - x) for 80 km and Rs. (1490 - x) for 90 km distance.

∴ Rate per km is given by -

On Cross multiplying, we get -

⇒ 90(1330 - x) = 80(1490 - x)

⇒ 119700 - 90x = 119200 - 80x

⇒ 10x = 500

⇒ x = 50

Hence, the fixed charge = Rs. 50

and, Rate per km = ((1330 - 50)/80) = (1280/80) = Rs. 16