Answer:
346.g of solution
Explanation:
In this case, if we have 5.2 % by mass it means that in <u>100 g of the solution we will have 5.2 g of glucose</u>. Therefore we can do the calculation:
<u>5.2 g of glucose = 100 g of solution</u>
So, if we need 8 g of glucose we had to have 346.15 g of solution
This logic can work for all types of solutions. By mass (as in this case), by volume or mass/volume.
I hope it helps!