Question

A car travels at $$45km$$ per hour. How much time will it take to cover $$90km$$ ?
1. $1$ hour
2. $$2$$ hours
3. $$3$$ hours
4. $$10$$ hours

Answer 1

Hint: First, we shall analyze the given information. It is given that a car travels at $$45km$$per hour. We are asked to calculate the time required by the car to cover$$90km$$.
It can be understood that the values of speed and distance are given in the question.
That is, it is given that speed $=$$$45{\displaystyle \frac{Km}{h}}$$
Distance$=$ $90km$
We need to just substitute the above values in the given formula.
Formula used:
 The formula to obtain the speed is as follows.
$$Speed={\displaystyle \frac{Distance}{Time}}$$
Since we are asked to calculate the time taken, we shall change the above formula as follows.
$Time={\displaystyle \frac{Distance}{Speed}}$

Complete step by step answer:
It can be understood that the values of speed and distance are given in the question.
That is, it is given that speed $=$$$45{\displaystyle \frac{Km}{h}}$$
Distance $=$$90km$
We are asked to calculate the time required by the car to cover$$90km$$.
Now, using the formula, we have,
$Time={\displaystyle \frac{Distance}{Speed}}$
Time = $${\displaystyle \frac{90\text{km}}{45\text{kmph}}}$$
After some simplification by dividing the terms we get
Time $$=2$$hours
Therefore, it will take two hours for the car to cover $$90km$$ which is the required answer.

So, the correct answer is “Option 2”.

Note: If required, first we need to convert the given units into our required units. Suppose we are asked to calculate the distance, we just convert the formula for our convenience.
That is,
$$Speed={\displaystyle \frac{Distance}{Time}}$$into
$$Speed\times Time=Dis\tan ce$$
The SI unit of speed is $m{s}^{-1}$ .
The SI unit of time is $s$ .
The SI unit of distance is $m$ .
The long distances are measured in kilometers.
Therefore, here in this question, it will take two hours for the car to cover $$90km$$.