Question

A car travels at a speed of 80 km/h. Which of the following is correct to convert the speed of the car to hm/s? [1 km = 10 hm, 1 h = 3600 s]
A divide 80 by 3600
B multiply 80 by 3600
C divide 80 by 10 and multiply the result obtained by 3600
D multiply 80 by 10 and divide the result obtained by 3600

Answer 1

Answer: The correct answer is Option D.

Explanation:

We are given that car travels with a speed of 80 km/hr and we need to convert it into hm/s.

For that we use the conversions:

1 kilometer = 10 hectometer

And, 1 hour = 3600 seconds

To convert the quantity into hm/s, we multiply the numerator which is 80 by 10 to convert the whole quantity into hm/hr and now, to convert the result into hm/s finally, we divide the result by 3600.

$\Rightarrow (\frac{80km1}{hr})(\frac{10hm}{1km})=\frac{80km}{hr}\\\\\Rightarrow (\frac{80km}{hr})(\frac{1hr}{3600s})=\frac{80hm}{3600s}$

Hence, the correct answer is option D.