Answer:
Class 7A collected 4.8 ounces of pure gold.
Step-by-step explanation:
Key skills required are: Percentages, Multiplication
Here we have to do 12% x 40 to find the number of oz of pure gold. We first have to convert 12% into a decimal. Divide it by a 100 (or move the decimal point 2 places to the left) and you will get 0.12.
Do 0.12 x 40 and you will get 4.8
Therefore, there are 4.8 oz of pure gold in Class 7A's gold sand