You have 100ml of 1/50 dilution of serum in saline. How much serum is present in that 100ml?

Answer 1

Another way to look at this question is to ask yourself what percent of 100ml of a serum/saline solution is serum. Since the serum was diluted in the saline, then the 1/50 dilution means that there is 1 part serum per 50 parts saline, or 1 part serum plus 49 parts saline. The way to calculate this mathematically is to set up a ratio:

1 x

— = —

50 100

Solving for x will give you the amount of milliliters out of the 100 that was serum, in this case, 2mL.

Therefore, making this solution required 2mL of serum and 98mL of saline.