David spent $75 on taxis, which were 15% of his total expenses on the trip. He therefore spent 75(100/15) = $500 on the trip altogether. The hotel and souvenirs make up 35% + 5% = 40% of his total expenses. 40% of 500 is $200.

This is a very basic form percentage question. This can be rewritten:

0.3 * x = 20

(Remember, the word "of" in a word problem indicates multiplication, while the word "is" indicates an equals sign).

Solve for x: x = 20 / 0.3 = 66.67

An algebraic expression for this item is:

If $76.50 had been collected after 18 students had paid, we can determine how much each student contributed:    

$76.50/18 = $4.25 per student

Now we can multiply this by the total number of students (26) to get the full price of the gift:

26 x $4.25 = $110.50

The first part of the problem tells us that x% of 20 is 50. We can model x% as x/100 or 0.01x. To find x% of 20, we can multiply 0.01x and 20. In other words, we can write the following equation:

(0.01x)(20) = 50

Divide both sides by 20.

0.01x = 2.5

Divide both sides by 0.01.

x = 250.

The question then asks us to find 20% of x. We can represent 20% as 0.2, and we know that x is 250. Therefore,

20% of 250 = 0.2(250) = 50.

The answer is 50.

Let x be the number in question.

Then 2/3 * x = 18.

x = 18 * 3/2 = 27

Now find 1/9 of 27:

1/9 * 27 = 3

The salesperson has already earned a commission of 16% of $82,000, which is equal to

.

This exceeds her goal for the week of $10,000, so she has already reached her goal.

Your share = 45% of 100 pounds of bacon = .45 * 100 = 45 pounds

For mom and cousin = 30% + 25% =  55%

Percent left for you = 100% - 55% = 45%

45% of 45 pounds = .45 * 45 = 20.25 pounds

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