George wishes to increase the percent of acid in 50ml of a 15% acid solution to 25% acid, how much pure acid must he add?

Let's use the decimal equivalent of percent. He has 50 ml of a 0.15 acid solution. He wants the concentration of acid to increase to 0.25 by adding pure acid.

concentration = (volume of acid)/(total volume of solution)

He takes the current solution and add x amount of pure acid.

15% of 50 ml = 7.5 ml

The current 15% solution contains 7.5 ml of pure acid. The x amount of acid he adds is added onto the 7.5 ml of acid he already has and it is also added to the total volume of 50 ml.

(7.5 + x)/(50 + x) = 0.25

7.5 + x = 0.25(50 + x)

7.5 + x = 12.5 + 0.25x

0.75x = 5

x = 6.6666...

6 2/3 ml

fist on the left goes with the third on the right. second on the left goes with the fourth on the right. third on the left goes with the second on the right. the fourth on the left goes with first on the right

median is the value separating the higher half of a data sample, a population or probablity distribution from the lower half.

step-by-step explanation:

say you have 3,8,7,3,1,9,8 order them from lowest to highest

if orderd it would be 1,3,3,7,8,8,9 now you take away from the lowest and the highest until you end up in the middle.

so you would remove the 1 and 9 leaving you with 5 digits remaining

when you've reached the middle that would be your answer so in this case the answer is 7

if there were two numbers left say 7 and 5 you'd and them together so 12 then divide by 2 witch would equal 6 so the answer would be 6

good luck on that project hoped i you at all