Question

two planes, which are 1965 miles apart, fly toward each other. their speeds differ by 55mph. if they pass each other other in 3 hours, what is the speed of each?​

Answer 1

The speed of the planes are 300 miles per hour and 355 miles per hour.

Solution:

Given, Two planes are 1965 miles apart, flying toward each other.  

Their speeds differ by 55 mph.  

They pass each other in 3 hours,  

We have to find what is the speed of each?

Let the speed of 1st plane be s miles per hour, then speed of the other plane will be s + 55 miles per hour.

And, distance travelled by 1st plane be d, then distance travelled by other plane will be 1965 – d miles

Now, we know that, distance = speed $\times$ time

So, for 1st plane ⇒ $\mathrm{d}=\mathrm{s} \times 3$

For 2nd plane ⇒ $1965-d=(s+55) \times 3$

By using 1st plane equation

1965 – 3s = 3s + 165  

1965 – 165 = 3s + 3s

6s = 1800

s = 300

So, speed of 1st plane is 300 miles per hour, then speed of 2nd plane  will  be 300 + 55 = 355 miles per hour.

Hence, the speed of the planes are 300 miles per hour and 355 miles per hour.