Answer:
2 hours: 27 miles, 3 hours: 40.5 miles, 3.5 hours: 47.25 miles
Step-by-step explanation:
1.) If a hiker hikes 9 miles in 2/3 of an hour, he will hike 4.5 (Half of 2/3 is 1/3 and half of 9 is 4.5) miles in 1/3 of an hour and 13.5 miles per hour. (1/3 times 3 gives us a whole and 4.5 times 3 is 13.5)
2.) 2 hours: 13.5 * 2 = 27 miles
3.) 3 hours: 13.5 * 3 = 40.5 miles
4.) 3.5 hours: 13.5 * 3.5 = 47.25 miles
1199.3 (I'm assuming you mean round to the nearest tenth)
Consider the attached ellipse. Let the sun be at the right focus. Then perihelion is at right vertex on the x-axis and aphelion is at the left vertex on the x-axis.
The distances:
- from perihelion to the sun in terms of ellipse is a-c;
- from aphelion to the sun in terms of ellipse is a+c.
Then

Add these two equations:
and subtract first equation from the second:
Note that
thus

The equation for the planet's orbit is

Answer:
8n
Step-by-step explanation:
By induction:
It's true for

, since

clearly contains a factor of 3.
Suppose it's true for

, that

is divisible by 3. Then

where

is an integer. This reduces to

and both terms are clearly multiples of 3. We know that

is an integer since we had set

previously, which implies

is a multiple of

. So the statement is true.