2007-03-03 10:18:48 · 4 answers · asked by Lucky 1 2 in Science & Mathematics ➔ Chemistry
You want to find how much is 21% of 400mL.
Therefore
21/100 = x/400
So you multiply 21/100 * 400 = x
x = 84 mL of acid is in the 400mL solution.
2007-03-03 10:24:19 · answer #1 · answered by Belle 3 · 0⤊ 0⤋
here is the mathematical way to solve it using proportions...
(X/400)=(21/100) Then you cross-multiply so...
8400=100X Divide 100X into 8400...
X=84
There are 84 millileters of acid in the solution.
2007-03-03 18:26:09 · answer #2 · answered by Renegade Of This Time and Age! 2 · 0⤊ 0⤋
21%
What is 21% of 400mL?
Multiply 21% (21/100) X 400mL
84mL
2007-03-03 18:32:55 · answer #3 · answered by BP 7 · 0⤊ 0⤋
multiply 400 by 21%, which is equal to 0.21
so 400*0.21=84ml
2007-03-03 18:20:52 · answer #4 · answered by MLBfreek35 5 · 0⤊ 0⤋