Math problemssssss?

Question

How many liters of a 50 % solution should be added to a 80% solution to obtain a 60% solution?

Answer 1

0.5x + 0.8y = 0.6(x + y)
5x + 8y = 6x + 6y
x = 2y
You need 2 liters of the 50% solution for every liter of 80% solution.

Answer 2

lets say that the total volume of the 60% solution is 100L
let x be the number of litres of the 50% solution
then 100-x would be the litres of the 80% solution:

0.5x + 0.8(100-x) = 0.6(100)
0.5x - 0.8x + 80 = 60
-0.3x = -20
x = 66.66667

which is 2/3 of the final solution
whatever amount of the 80% solution used, 2 times that amount needs to be added of 50% solution

Answer 3

it depends on how much solution there is originally. for example if you have an 80% solution that is only 1 mL then you would not add 2 liters to it to make a 60% solution. so you need more information to do the problem.

Answer 4

How many liters of 80% solution are there?

Lets say there are y liters of 80% solution and x liters of 50% solution.

then we need to make two equations since we have two variables.
but we only have enough information to make one equation. the other equation needs to have something to do with the total volume of the final solution or the volume of one of the solutions you're mixing. I imagine that the question gave you a specific amount of 80% solution but you neglected to include it here. it doesn't matter just plug it in for y and you'll be fine.

so we have x amount of 50% and y amount of 80% and we want to get a 60% solution. Let's just say that the solution is of Chemical-x.
So to calculate the total amount of Chemical-x in our final solution we have the following formula .50x+.80y. To get the percentage of Chemical-x in our final solution we need to divide this by the total volume which is x+y. So the formula to calculate the percentage of our final solution is (.50x+.80y)/(x+y) and we want that final percentage to be 60% so we get the equation (.50x+.80y)/(x+y)=.60
Now let's solve it as best we can.
First step: multiply by (x+y)
(.50x+.80y)=.60(x+y)
Distribute the .60
.50x+.80y=.60x+.60y
subtract .60y and .50x
.20y=.10x
divide by .10
2y=x
So you need twice as much 80% solution as 50% solution

Answer 5

2. Then the average and therefore resulting % will be 60%.

Answer 6

you're able to desire to establish a proportion. 5/3=7.5/x -go multiply 5*x=3*7.5 5x=22.5 -Now divide by using 5 to isolate the variable 5x/5=2.5/5 x=4.5 the dimensions of the shorter piece is 4.5 meters

Answer 7

2 liters.

Answer 8

umm...
maybe two liters of 50% solution
maybe

Answer 9

4 dollars

Answer 10

two