Two planes left simultaneously from the same airport and headed in the same direction towards another airport 1800 km away. the speed of one of the planes was 100 km/hour slower than the speed of the other plane, and so it arrived at its destination 36 minutes after the faster plane. find the speeds of both planes.

Faster plane --> 600km/hr

Slower Plane --> 500km/hr

Step-by-step explanation:

Use inequality: 1800/r = 1800/(r-100) + 3/5 and solve to get r = 600, so the plane which is r -100 is 500 km/hr.

We conclude that the daily average revenue was actually $675.

Step-by-step explanation:

We are given that the  current owner claims that over the past 5 years, the average daily revenue was $675 with a standard deviation of $75.

A sample of 30 days reveals a daily average revenue of $625.

Let = daily average revenue.

So, Null Hypothesis, : = $675     {means that the daily average revenue was $675}

Alternate Hypothesis, : $675     {means that the daily average revenue was different from $675}

The test statistics that would be used here One-sample z test statistics as we know about the population standard deviation;

                       T.S. =    ~ N(0,1)

where, = sample daily average revenue = $625

             = population standard deviation = $75

            n = sample of days = 30

Since, we are given that we have decided not to reject the null hypothesis which leads us to the conclusion that the daily average revenue was actually $675.