Suppose you add x liters of pure water to the 10 L of 25% acid solution. The new solution's volume is x + 10 L. Each L of pure water contributes no acid, while the starting solution contains 2.5 L of acid. So in the new solution, you end up with a concentration of (2.5 L)/(x + 10 L), and you want this concentration to be 10%. So we have
and so you would need to add 15 L of pure water to get the desired concentration of acid.
Is this asking for the slope?
Y=-10x+60
You do rise/run which is -20/2, so -10
Then just find the y-intercept, which is 60.
If it was in standard notation it would be very confusing to add the number of cells and it would be less organized.
X=6
y=7
6+7
= 13
1/2(6) + 7
= 3 +7
=10
C is correct.
1. You do 12.99 times 3
2. $0.69 times 2
3. Add $2.99 to the two prices above
4. Add the $2.52 tax to the prices
And you should get around $45 and some change
