<h3>
Answer: 2.5 hours</h3>
This is equivalent to 2 hours, 30 minutes
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Explanation:
x = number of hours
Let's say we have two plans A and B. Plane A travels 540 km/hr and let's make it travel eastward. Plane B would travel the opposite direction (west) at 520 km/hr.
After x hours, plane A travels 540x kilometers. Plane B travels 520x km after the same amount of time, since it takes off at the same time plane A does.
In total, the distance between the two planes after x hours is 540x+520x = 1060x kilometers.
Set this equal to 2650 and solve for x
1060x = 2650
1060/1060 = 2650/1060 ... divide both sides by 1060
x = 2.5
It takes 2.5 hours for the two planes to be 2650 km apart.
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side note:
2.5 hrs = 2 hrs + 0.5 hrs
2.5 hrs = 2 hrs + (0.5 hrs)*(60 min/1 hr)
2.5 hrs = 2 hrs + 30 min
2.5 hrs = 2 hrs, 30 min
