Answer:
![h=40t+9700](https://tex.z-dn.net/?f=h%3D40t%2B9700)
where the elevation, h, is in feet and time, t, is in minutes.
Step-by-step explanation:
At the time,
min, the elevation,
feet and
at the time
min, the elevation,
feet.
As they are hiking a steady incline, so the change in the elevation with respect to time will be constant.
So, there will be a linear relationship between the elevation and the time.
Let
be the elevation at any time instant
, so the linear relation among these quantities is
![h=mt+C_0\;\cdots(i)](https://tex.z-dn.net/?f=h%3Dmt%2BC_0%5C%3B%5Ccdots%28i%29)
where
is the rate of change of elevation with respect to time and
is constant.
The change in the elevation,
feet.
and the change in time,
min.
So, change in the elevation in unit time,
feet/min.
Now, from equation (i)
![h=40t+C_0](https://tex.z-dn.net/?f=h%3D40t%2BC_0)
As the elevation,
at time
, so
![10,300=40\times15+C_0](https://tex.z-dn.net/?f=10%2C300%3D40%5Ctimes15%2BC_0)
![\Rightarrow C_0=9700](https://tex.z-dn.net/?f=%5CRightarrow%20C_0%3D9700)
Hence, the required equation is
![h=40t+9700](https://tex.z-dn.net/?f=h%3D40t%2B9700)
where the elevation,
, is in feet and time,
, is in minutes.