If I want to make a solution that has a 5% concentration of salt, is it correct for me to have 380mL water and 20g salt?

Question

My method behind this was that I wanted a 400g solution, and so since 1mL water is equal to 1g water, I did:

400x0.95=380g water or 380mL water
and
400x0.05=20g salt

Is this correct? If not, why and what would be the correct way to find this?

Answer 1

I found this on the internet, is it correct?

"The easy way to remember how to do % problems is to always remember that % means parts per HUNDRED. So, a 25% salt solution (if it is weight/volume) means 25 grams per 100 mls. Then, if you want only 50 mls, you would use 12.5 grams in 50 mls. If you want only 10 mls of solution, you would use 2.5 grams in the 10 mls. And so forth."

Answer 2

I need to do experimenting for a lab and I only have the scale for the rest of today so I really need an answer so I can start the experiment! It's a simple yes or no!