simplify x y x y

ATI TEAS 7

TEAS Test Math Questions

1. Simplify (x^2 - y^2) / (x - y)

A. x + y
B. x - y
C. 1
D. (x + y)/(x - y)

Correct answer: A

Rationale: The expression 𝑥^2 - 𝑦^2 is a difference of squares, which follows the identity: 𝑥^2 - 𝑦^2 = (𝑥 + 𝑦)(𝑥 - 𝑦). Therefore, the given expression becomes: (𝑥^2 - 𝑦^2) / (𝑥 - 𝑦) = (𝑥 + 𝑦)(𝑥 - 𝑦) / (𝑥 - 𝑦). Since (𝑥 - 𝑦) appears in both the numerator and the denominator, they cancel each other out, leaving 𝑥 + 𝑦. Thus, the simplified form of (𝑥^2 - 𝑦^2) / (𝑥 - 𝑦) is 𝑥 + 𝑦. Therefore, the correct answer is A (x + y). Option B (x - y) is incorrect as it does not result from simplifying the given expression. Option C (1) is incorrect as it does not account for the variables x and y present in the expression. Option D ((x + y)/(x - y)) is incorrect as it presents the simplified form in a different format than the correct answer.

2. A cell has a diameter of 0.1 meter, and another cell has a diameter of 0.05 meters. How many times larger is the first cell compared to the second cell?

A. 2
B. 4
C. 8
D. 16

Correct answer: A

Rationale: To determine how many times larger the first cell is compared to the second cell, divide the diameter of the first cell by the diameter of the second cell: 0.1 / 0.05 = 2. Therefore, the first cell is 2 times larger than the second cell. Choice B, C, and D are incorrect because they do not provide the accurate calculation for the size difference between the two cells.

3. A patient is prescribed 5 mg of medication per kilogram of body weight. If the patient weighs 60 kg, how many milligrams of medication should the patient receive?

A. 100 mg
B. 150 mg
C. 300 mg
D. 400 mg

Correct answer: C

Rationale: The correct calculation to determine the medication dosage for a patient weighing 60 kg is: 5 mg/kg x 60 kg = 300 mg. Therefore, the patient should receive 300 mg of medication. Choice A (100 mg) is incorrect as it does not account for the patient's weight. Choice B (150 mg) is incorrect as it miscalculates the dosage. Choice D (400 mg) is incorrect as it overestimates the dosage based on the patient's weight.

4. Simplify the following expression: 0.0178 × 2.401

A. 2.0358414
B. 0.0427378
C. 0.2341695
D. 0.348324

Correct answer: B

Rationale: To simplify the expression 0.0178 × 2.401, you multiply the two numbers to get the result. Therefore, 0.0178 × 2.401 = 0.0427378. Choice A (2.0358414), Choice C (0.2341695), and Choice D (0.348324) are incorrect as they do not represent the correct result of the multiplication operation.

5. Which of the following describes a proportional relationship?

A. Johnathan opens a savings account with an initial deposit of $150 and deposits $125 per month
B. Bruce pays his employees $12 per hour worked during the month of December, as well as a $250 bonus
C. Alvin pays $28 per month for his phone service plus $0.07 for each long-distance minute used
D. Kevin drives 65 miles per hour

Correct answer: A

Rationale: A proportional relationship is one in which two quantities vary directly with each other. In choice A, the amount deposited per month is directly proportional to the initial deposit. The relationship can be represented as y = 125x + 150, where x is the number of months and y is the total amount in the account. Choices B and C involve additional fixed amounts or variable costs that do not maintain a constant ratio, making them non-proportional relationships. Choice D refers to a constant speed of driving, which is not a proportional relationship as it does not involve varying quantities that change in direct proportion.