A planet has a circular orbit around a star. It is a distance of 74,000,000 km from the centre of the star. It orbits at an average speed of 38,000 km/h. How many Earth days does it take the planet to orbit the star? Give your answer to 2 sf.

81.14 Earth days.

Step-by-step explanation:

Step 1

The formula to solve this question is given as

Speed = Distance / Time

In the question, we are given the following values

Distance of the planet = 74,000,000 km

Average Speed of the planet = 38,000 km/h.

Average Speed = Distance / Time

38,000 km/h = 74,000,000 km/ Time

Cross Multiply

38,000 km/h × Time = 74,000,000 km

Divide both sides by 38,000 km/h

Time(hours) = 74,000,000 km /38,000 km/h

Time(hours) = 1947.3684211 hours

This means the circular orbit of the planet around the star takes 1947.3684211 hours.

Step 2

In the question, we were asked to find how many Earth days it takes.

Hence, it is known that

24 hours = 1 (Earth) day

1947.3684211 hours = x days

We would cross Multiply

24 hours × x days = 1947.3684211 hours.

Divide both sides by 24 hours

x days = 1947.3684211 hours ÷ 24 hours

x days = 81.140350879 Earth days.

Therefore, the number of Earth days it takes the planet to orbit the star to 2 significant figures =

81.14 Earth days.

all it means is function 3