Answer:
k = 3.75 or 3 3/4
Explanation:
=

This can be solved using cross multiplication. Multiply 3 by 5 and then 4 by the variable k.
3 x 5 = 15
4 x k = 4k
Both of these numbers (15 and 4k) can be set up into an equation.
4k = 15
4k/4 = 15/4
k = 3.75 or 3 3/4