Question

How long would it take to bicycle 45 miles at an average speed of 15 miles per hour?

Answer 1

We start solving the problem by assuming the variables for the distance travelled, speed of bicycle and time taken to travel. We then substitute all these values in the formula $speed\left( v \right)=\dfrac{\text{distance}\left( d \right)}{time\left( t \right)}$ to proceed through the problem. We then make the necessary calculations to get the required value of the time taken to travel by bicycle.

Complete step-by-step answer:
According to the problem, we are asked to find the time taken to ride a bicycle for 45 miles if its average speed is 15 miles per hour.
Let us assume the distance needs to be travelled be ‘d’. So, we have $d=45$ miles. Also, the speed of the bicycle be ‘v’. So, we have $v=15$ miles/hour. And the time required is ‘t’ hours.
We know that $speed\left( v \right)=\dfrac{\text{distance}\left( d \right)}{time\left( t \right)}$. Let us substitute all the required values in this equation to get the time taken for the bicycle.
So, we have $15=\dfrac{45}{t}$.
$\Rightarrow t=\dfrac{45}{15}$.
$\Rightarrow t=3$ hours.
So, we have found the time taken to travel 45 miles by a bicycle with an average speed of 15 miles per hour is 3 hours.
$\therefore$ The time taken by the bicycle to travel 45 miles is 3 hours.

Note: Whenever we get this type of problems, we first recall the required definition or formulas to get the required answer. We should check the units of the speed and distance before solving the problem as this will change the final required answer of time. Similarly, we can expect problems to find the time taken by bicycle to travel 45 miles if its average speed is 10 kilometres per hour.