Hi, I've been doing some practice papers to revise for my Biology exam (tomorrow! ) and I came accross one question about percentages...I thought it was alright at first, but looked at the mark scheme and apparently I was wrong.
Please help! this is probably really easy for you all! lol
Anyway, the question was:
Calculate the percentage difference between the concentration of Potassium ions in the culture solution at the start of the experiment (8.0) and the concentration of potassium ions in the barley solution (42.0)
According to the mark scheme I had to first do 42-8. Which I did, and got 34. But thats where I get stuck!
It says that the answer to the question is 425%. But how on earth did they work that out? is there even such a thing as 425%??? lol