Answer
$0.88\ {}^{\circ}C$
Work Step by Step
Solving Variation Problems (see p. 424)
1. $\ \ $Write an equation that models the given English statement.
2. $\ \ $ Substitute the given pair of values into the equation in step 1 and find the value of k, the constant of variation.
3. $\ \ $Substitute the value of k into the equation in step 1.
4. $\ \ $Use the equation from step 3 to answer the problem's question.
-----------
Let T be the water temperature $({}^{\circ}C)$ , d the depth (m).
1.
$T$ varies inversely as $d,\ \displaystyle \qquad T=\frac{k}{d}$
2.
$4.4=\displaystyle \frac{k}{1000}\qquad /\times 1000$
$4400=k$
3.
$T=\displaystyle \frac{4400}{d}$
4.
$d=5000,T=?$
$T=\displaystyle \frac{4400}{5000}=0.88{}^{\circ}C$