Assuming that the earth describes in one year a circle, of 92500000 miles radius, whose centre is the sun, how many miles does the earth travels in a year?

Hint: We will use the following conversions, the circumference of the circle is $2\pi r$ where r is the radius of the circle, which is 92500000 miles. So, the distance covered by the earth will be equal to the circumference of the circle.

Complete step-by-step answer:
It is given in the question that we have to assume that earth describes in one year a circle of radius 92500000 miles. Also, the sun is at the centre of that circle.
Now, we have to find the distance travelled by earth in a complete year. So, it is clear that the distance travelled by earth in a complete year will be equal to the circumference of the circle. Now, we know that circumference of the circle is given by
$circumference=2\pi \times radius$, we have $radius=92500000miles$, taking $\pi =3.14$ and C as the circumference of the circle that earth inscribed in one complete year, we get circumference of circle,
$C=2\times 3.14\times 92500000$ that is,
$=6.28\times 92500000$ miles
$=580900000miles$.
Therefore, the distance covered by the earth in a complete year around the sun is 580900000 miles.

Note: This is a very basic question and students may put the wrong number of zeros while performing the calculation which completely changes our answer. Or, students may copy different numbers of zeros from the question. Thus, it is recommended to put all the zeros very carefully and do calculations step by step, otherwise the question is very easy, if it comes in the examination.