How many grams each of a 10% salt solution and a 5% salt solution must be mixed in order to obtain 400g of an 8% solution?

I dont want to give you the exact equation so u wont be copying- here is an example.

let x=grams of salt that you already have

let y=grams of salt that need to be added

let z=total amount of salt in the solution after adding salt

We know that salt makes up 25% of the 400g solution, and that 25% can also be written as .25. Thus, we can write an equation to determine x's value:

x=.25*400g

x=100g

Therefore, there are 100 grams of salt already in the solution.

Now that we've determined x's value, we'll bring z into the equation. There are two ways to calculate z. z is equivalent to the sum of x and y. Remember, x is equal to 100 grams. So, z's equation is as follows:

z=100g+y

The other way to calculate z is as a percentage of the final solution. As the question states, we want the final solution to have a salt content of 40% (which we can write as .40). The final amount of solution can be written as below:

400g+y=total amount of solution after adding salt.

This is because we are adding y (the amount of salt needed to bring the salt content to 40 percent)to the amount of solution which we already have.

Therefore, the second way to express z is below:

z=.40*(400g+y)

After we have two equations for z, we can set them equal to each other as follows:

100g+y=.40*(400g+y)

We then can distribute the .40 over the parenthesis.

100g+y=160g+.40y

And then we can subtract 100 grams from both sides of the equation.

y=60g+.40y

Next, we subtract .40 y from both sides of the equation to get y on one side.

.6y=60g

Finally, we can divide both sides by .6 to isolate y.

y=100g

Therefore, you must add 100g of salt to the solution to make it 40 percent salt.

DID I DO IT RIGHTT?? pls tell me

geometry: triangles

solvers

lessons

answers archive

call the larger triangle abc

then the smaller triangle cde is similar to abc (all angles are equal, aaa).  

ab is the side that is 36, and we wish to find de, the side corresponding to ab

area_cde = area_abc - area_cde --> area_abc / area_cde = 2

let x=length of de

ratio of areas = (ratio of sides)^2

+2+=+%2836%2fx%29%5e2+

+2+=+1296%2fx%5e2+

++x%5e2+=+1296%2f2+=+648+

25.45584

you need to add a picture