The final solution is going to have a concentration of twenty-five percent and a volume of 10 liters. The amount of sucrose in the solution is equal to the concentration (expressed as a decimal) multiplied by the total volume. Therefore, the final solution will have 25% • 10 = 0.25 • 10 = 2.5 liters of sucrose.

Let x be the amount of the solution that is removed and then replaced by the forty percent solution. The amount of twenty percent solution that will remain will be equal to 10 – x, because the final solution will still have ten liters. (The amount removed is replaced with the same amount, so the final volume of the solution is the same.)

So we have to get 2.5 liters of sucrose from the twenty percent solution and the forty percent solution combined. The amount of sucrose we will get from the twenty percent solution equals the volume of the twenty percent solution (which we established will be 10 – x) multiplied by twenty percent as a decimal.

Amount of sucrose from 20% solution = 0.20 • (10 – x)

The amount of sucrose we get from the forty percent solution will equal the product of x and forty percent (since we defined x as the amount of forty percent solution).

Amount of sucrose from 40% solution = 0.40x

Now, we need to add the amount of sucrose from the 20% and the 40% solutions, and then set this equal to 2.5, because ultimately we will have 2.5 liters of sucrose in the solution. We can write the equation as follows and then solve for x:

0.20 • (10 – x) + 0.40x = 2.5

Here is a table that we can also use to summarize the information discussed above.

0.20 • (10 – x) + 0.40x = 2.5

Distribute.

2 – 0.2x + 0.4x = 2.5

Combine x terms.

2 + 0.2x = 2.5

Subtract 2 from both sides.

0.2x = 0.5

Divide both sides by 0.2.

x = 2.5 liters

The answer is 2.5 liters. 

60% of 200,000 is 120,000

0.6 * 200,000 = 120,000

If Becky received 60% of the vote, Jason must have received 40% of the vote. 40% is equal to 0.40. By multiplying the number of votes times the percentage, we can calculate how many votes Jason received.

0.40 * 30 = 12.

After I eat 30% of the pizza, 70%, or 0.7, is left. Sally eats 20%, or 0.2 of that. So to compute how much of the original pizza Sally has eaten, we must multiply 0.7 by 0.2. We will arrive with 0.14 or 14%. Thus we subtract my the 30% of the pizza I ate and the 14% of the pizza Sally ate from 100% or the original whole, and we will arrive with 56%.

1. 20% of Carla's whole budget is equal to $200. With this information, one can find Carla's weekly budget.

Set up the equation: 0.2b = 200 (b = budget).

b = 200/0.2 = 1000 = Carla's weekly budget

2. To find the amount Carla spends for rent, one needs to find what 35% of $1000 is.

0.35 x 1000 = 350

3. Because Carla spends 35% of her total budget on rent, she spends $350 on rent.

If p is the number of pounds of cargo that is initially on the ship and m is the number of pounds of cargo that we transfer (or remove from the ship), we can find how many pounds of cargo are still on the ship after the transfer by the expression p – m. In order to model this as a percent, we would have to form a fraction, using the initial pounds of cargo, p, as the whole amount and p – m as the fractional part. 

So,

we would get  as our fraction. 

However, this problem asks us to find the percent, so we would simply multiply by 100

 will get our answer into percent form.

We first subtract the 100 cars that Gor sold from the total of 250 sold. We are left with 150 cars, and we know that Levon sold 62% of them. 100% – 62% = 38%. Hence, Raffi sold 38% of 150 cars. 150 * 0.38 = 57

You must first determine the percentage of the students in chorus. To do this, subtract the other percentages from 100: 100 – (35 + 29 + 24) = 12.

Therefore, 12% of the 400 students at this school attend chorus.

To determine the number of students in the chorus, multiply .12 (12%) by 400.

0.12(400) = 48

There are two ways to solve this problem. 

First, we can convert the given percentage to a decimal and multiple by the whole. 

16% = 0.16

Secondly, we could set up a proportion. We are given the whole from which a percentage is taken, so we can say:

To solve, cross multiply and simplify.

Let's set up a proportion to solve this problem, where  represents the number of copies sold in the U.S. Remember that we can express  as a fraction.

Now, we can solve for the unknown by cross-multiplying.