Question

The initial speed of a car is 10 km/h. Every minute the speed of the car increases by 50% of the initial speed. Which graph best suits the relationship between time and speed of the car?

• A. None
• B. Graph 3
• C. Graph 2
• D. Graph 1

Answer 1

The correct option is C Graph 2

Given:

Initial speed of the car = 10 km/h

Increase in speed by 50% for every minute.

Representing the above information in a table, we get:

Time (in min)	Speed of the car (in km/h)
$0$	$10$
$1$	$10+50\%of10=10+5=15$
$2$	$15+50\%of10=15+5=20$
$3$	$20+50\%of10=20+5=25$

All the points, i.e, (0,10), (1,15), (2,20), and (3,25) lies on Graph 2.

Therefore, Graph 2 is the correct answer.


Let's plot the other two graphs:


These graphs are not correct.

So, only Graph 2 shows the correct condition.