6. A certain chemical reaction needs 20 grams of hydrochloric acid. You have a bottle of 12% solution of hydrochloric acid (by weight). How many grams of solution will you need to use in order to get 20 grams of acid?

To find out what you need to multiply times 12% to get 20 grams, we need to divide. Divide 12% into 20. Remember to turn the 12% into a decimal before dividing.

Move the decimal out of the divisor, and move it the same number of places in the dividend, and complete the division.