This is a straightforward percentage problem. After the first discount, the price of the weights is $0.8X. This price is then further reduced by 10% for the employee discount. 90% of 0.8X = 0.9(0.8X) = 0.72X.

The easiest way to solve this is to note that a 30% markdown reduces the cost to 70% of the original cost.  Likewise, a 40% markup is the same as making the price 140% of its current value.  Using this, we can solve our problem in one string of multiplications:

New cost = Original * 0.7 * 1.4 * 0.9

New cost = 20 * 0.7 * 1.4 * 0.9 = 17.64

To find 25% of $50 you multiply 50 and 0.25. This gives you 12.50. This means the dress is $12.50 cheaper, so it now costs 50 – 12.50 = $37.50. You have an additional 10% off, so you multiply 37.50 by 0.10 to get 3.75. 37.50 – 3.75 = $33.75. This is the cost of the dress. NOTE: You CANNOT add 25% and 10% and take 35% off of the $50 dress. You will get the wrong answer. 

To calculate a 30% increase in cost, you can multiply the base cost by 1.3; therefore, if we are going to increase the rate five times, we will multiply by 1.3 five times, which is the same as 1.3⁵. The cost of creating 100 units per hour is 27 * 1.3⁵ = 100.25. 

If we want to make a 25% profit, we can set up the equation:

Price = 1.25 * 100.25 or 125.3125. To make at least a 25%, this will be $125.32.

First let's calculate what 70% of $1.29 is: .7(1.29) = .9

Next, calculate how much 4 cones would have cost at the original price vs. the sale price:

4(1.29) = 5.16

4(.9) = 3.60

5.16 – 3.60 = $1.56 saved

The sweater price starts at $36. Alice pays $36 – (.25 * $36) = $27. Chelsea then pays $27 – (.15 * $27) = $22.95, which is the correct answer.

When solving percentage questions such as this one, do NOT try to add up the discounts and find the final sale price all in one step. If you tried to do that here, the answer would have been $36 – (.25 + .15) * $36 = $21.60. This is an answer choice, but the wrong answer!  Most GRE percentage questions will always give you this as one of your answer choices to try and trick you!

18% of the dress is .18 * 50 = $9.  Then the sweater costs $50 + $9 = $59.

Based on the shirts label, Jenny should pay of the full price. With the store's discount, she will pay  of this. Thus, she will pay  of the full price. This is equivalent to . 

Since no price is given, you can pick $100 as the starting point for the value of the truck. $100 marked up 30% is $130, and the 30% discount brings it to $91.

Let's begin by finding the absolute amount necessary for a 27% profit. Following that, we will adjust for the needs of having a whole number price.  If the sale price is S, we can set up the following equation:

(S – 23)/23 = 0.27

S – 23 = 6.21

S = 29.21

The product must, however, be sold for at least $30 because it has to be an integer value.