drove from rich to boston at avg speed of 50 mph,if it took 5 hrs to drive from rich to phila at an avg speed of 70 mph and if the whole trip took 13 hrs how far is it from phila to boston?

Answered earlier today:

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"Rich?" Is that supposed to be Richmond VA?

Rich to Phila distance = 70x5 = 350 miles

Boston to Phila distance = X

(X + 350)/13 = 70 mph

Solve for X

To find the distance from Philadelphia to Boston, we can use the formula: Distance = Speed * Time.

First, let's calculate the distance from Richmond to Philadelphia:

Time = 5 hours
Speed = 70 mph

Distance from Richmond to Philadelphia = Speed * Time
Distance from Richmond to Philadelphia = 70 mph * 5 hours
Distance from Richmond to Philadelphia = 350 miles

Now, we need to find the distance from Philadelphia to Boston. We are given that the entire trip took 13 hours and the distance from Richmond to Philadelphia is 350 miles.
Since the total trip took 13 hours and the Richmond to Philadelphia leg took 5 hours, it means that the Philadelphia to Boston leg took 13 - 5 = 8 hours.

We know the average speed on the entire trip was 50 mph. Thus, to find the distance from Philadelphia to Boston, we can use the formula:

Distance = Speed * Time

Distance from Philadelphia to Boston = 50 mph * 8 hours
Distance from Philadelphia to Boston = 400 miles

Therefore, the distance from Philadelphia to Boston is 400 miles.