• Problem:
m varies jointly as I and n, m = 13 when I = 39 and n = 3.
• Solution:
Let's find the value of the constant, k, of the given joint variation. We can use the formula m = kln or simply, k = m/(ln).
[tex] \large \boxed{ \begin{array}{} \tt m =kln \\ \tt 13 = k(39)(3) \\ \tt 13 = 117k \\ \tt k = \frac{13}{117} \\ \tt k = \frac{1}{9} \end{array}}[/tex]
• Thus, the constant, k, of the given variation is 1/9.
