There are different time zones in the world due to the Earth's rotation as this results in different parts of the Earth receiving sunlight at different times.
GMT is used as a basis to find the times of other zones.
A real world expression would be Toby had makes 3 dollars per hour he wants to buy a ps4 for 40 dollars. he already has 10 dollars. how many hours does he have to work to afford his ps4. 3x+10=40
