Question

A chemist is using 336 milliliters of a solution of acid and water. If 19.4 % of the solution is acid, how many milliliters of acid are there? Round your answer to the nearest tenth.

Answer 1

65.2 milliliters

Explanation:

The quantity 336 milliliters is the 100% of the solution. We can represent this information on a table:

Milliliters Percentage of solution

336 ⇔ 100%

we are told that 19.4% of this solution is acid, and we need to know how many milliliters represents this percentage. I will call the number of milliliters of acid on the solution 'x', and updating the last table:

Milliliters Percentage of solution

336 ⇔ 100

x ⇔ 19.4%

We can solve this problem for 'x' using the rule of three which is to multiply the cross quantities on the table (336 by 19.4) and then divide by the remaining amount (100):

x = 336(19.4)/100

x = 6,518.4/100

x = 65.184

which rounding to the nearest tenth is: 65.2 milliliters