Answer
$\$ 3.10$ when the towel costs $\$ 0.10$
Work Step by Step
We need to set up a proportion in order to solve $x$.
$\dfrac{1.4}{(2.5)^2\pi-(1)^2\pi}=\dfrac{x}{(3.5)^2 \pi-(1)^2\pi}$
or, $\dfrac{1.4}{5.25\pi}=\dfrac{x}{11.25\pi}$
or, $5.25\pi x=15.75\pi$
After solving , we get $x=\$ 3$
Thus, the total cost is $\$ 3.10$ when the towel costs $\$ 0.10$.
