Question

It takes the Sun about $2.3\times {10}^8$ years to orbit the center of the Milky Way. It takes Pluto about $2.5\times {10}^2$ years to orbit the Sun. How many times does Pluto orbit the Sun while the Sun completes one orbit around the Milky Way?

Answer 1

Step1. Write all the information which is given and required to solve the answer.

It takes the Sun about $2.3\times {10}^8$ years to orbit the center of the Milky Way.

It takes Pluto about $2.5\times {10}^2$ years to orbit the Sun.

Step2. Now to find out how many times does Pluto orbit the Sun while the Sun completes one orbit around the Milky Way,

we should divide time taken by Sun to complete one orbit around the milky way by time taken by Pluto to complete one orbit around sun.

No. of times Pluto orbit the Sun while the Sun completes one orbit around the Milky Way = $(2.3\times {10}^8)÷(2.5\times {10}^2)$

Step3. To find out how many times does Pluto orbit the Sun while the Sun completes one orbit around the Milky Way, we need to solve the given expression

= $(2.3\times {10}^8)÷(2.5\times {10}^2)$

= $(2.3÷2.5)\times ({10}^8÷{10}^2)$ (dividing digits and powers simultaneously)

=$0.92\times {10}^{8-2}$

=$0.92\times {10}^6$

Hence, No. of times Pluto orbit the Sun while the Sun completes one orbit around the Milky Way = $9.2\times {10}^5$