Question

How many ounces of water must be added to 100 oz. of 60% iodine solution to produce a 55% solution? Round your answer to the nearest hundredth.

Answer 1

Given:

A 100 oz. of 60% iodine solution

We need to add the water to get a 55% solution

Let the number of ounces of water = x

There is an inverse relationship between the percentage of solution and the total amount

So, after adding x ounces, there is (x+100) oz. of the solution

We can write the following ratio:

$\frac{x+100}{100}=\frac{60}{55}$

Solve for x, use the cross product:

$\begin{gathered} x+100=\frac{60*100}{55} \\ \\ x=\frac{60*100}{55}-100=9.0909 \end{gathered}$

Rounding to the nearest hundredth

So, the answer will be 9.1 oz.