Answer:
We must add 400 ml of water.
Step-by-step explanation:
We can use the following equation:

Where:
- C(i) is the initial concentration of the solution (80%)
- C(f) is the final concentration of the solution (30%)
- V(i) is the initial volume (150 ml)
- V(f) is the final volume
Now, we just need to solve the equation for V(f).



Therefore, we must add 400 ml of water.
I hope it helps you!
Answer:
My best guess will have to be B
Step-by-step explanation:
i remember this question
Answer:
5.) b = -2/5 (or -0.4 in decimal form)
6.) 20.5
(I'm not totally sure but there may be someone else with a more accurate/correct answer.)
Here is what I got (Red represents my work, blue represents to follow which steps and highlighter represents what the answer is):