Nursing Elites

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. What is the formula to find the circumference of a circle?

• A. Circumference = 2πr
• B. Circumference = πr²
• C. Circumference = 2r²
• D. Circumference = r²π

Correct answer: A

Rationale: The correct formula to find the circumference of a circle is C = 2πr, where C represents the circumference and r is the radius of the circle. Choice B, Circumference = πr², represents the formula for the area of a circle rather than the circumference. Choice C, Circumference = 2r², is incorrect as it does not involve π in the formula. Choice D, Circumference = r²π, has the terms reversed compared to the correct formula; the formula should start with the constant (2) multiplied by π, followed by the radius.

3. How do you convert Fahrenheit to Celsius and Celsius to Fahrenheit?

• A. Fahrenheit to Celsius: Subtract 32, then divide by 1.8; Celsius to Fahrenheit: Multiply by 1.8, then add 32
• B. Fahrenheit to Celsius: Subtract 32, then divide by 2; Celsius to Fahrenheit: Multiply by 1.8, then add 20
• C. Fahrenheit to Celsius: Multiply by 2, then add 32; Celsius to Fahrenheit: Subtract 32, then divide by 1.8
• D. Fahrenheit to Celsius: Subtract 30, then divide by 1.8; Celsius to Fahrenheit: Multiply by 2, then add 32

Correct answer: A

Rationale: To convert Fahrenheit to Celsius, you start by subtracting 32 from the Fahrenheit temperature and then divide the result by 1.8. This formula accounts for the freezing point of water at 32°F and the conversion factor to Celsius. To convert Celsius to Fahrenheit, you multiply the Celsius temperature by 1.8 and then add 32. This process takes into consideration the conversion factor from Celsius to Fahrenheit and the freezing point of water. Choice B is incorrect as dividing by 2 instead of 1.8 would yield an inaccurate conversion. Choice C is incorrect as it involves incorrect operations for both conversions. Choice D is incorrect as subtracting 30 instead of 32 for Fahrenheit to Celsius and multiplying by 2 instead of 1.8 for Celsius to Fahrenheit would provide incorrect results.

4. Which of the following is the independent variable in the equation below? f(t)=4t+9

• A. f
• B. 9
• C. t
• D. 4

Correct answer: C

Rationale: The independent variable in a function is the variable that is being manipulated or changed to obtain different values. In the equation f(t) = 4t + 9, the variable 't' is the independent variable. It is the variable that the function f(t) depends on, and changing its value will result in different outputs for the function. The other choices, 'f', '9', and '4', are not the independent variable as they do not represent the variable that is being manipulated to determine the function's output.

5. A piece of wood that is 7 1/2 feet long has 3 1/4 feet cut off. How many feet of wood remain?

• A. 4 1/4 feet
• B. 4 1/2 feet
• C. 3 1/2 feet
• D. 3 3/4 feet

Correct answer: A

Rationale: To find the remaining length of wood, you need to subtract 3 1/4 feet from 7 1/2 feet. When you subtract the fractions, 7 1/2 - 3 1/4, you get 15/2 - 13/4 = 30/4 - 13/4 = 17/4 = 4 1/4 feet. Therefore, the correct answer is 4 1/4 feet. Choice B (4 1/2 feet) is incorrect because the subtraction result is not 1/2. Choice C (3 1/2 feet) is incorrect as it does not match the correct result of 4 1/4 feet. Choice D (3 3/4 feet) is also incorrect as it does not align with the correct answer obtained from the subtraction of fractions.

Similar Questions