Nursing Elites

1. A lab needs 200ml of a 5% salt solution. They only have a 10% solution. How much 10% solution and water should be mixed?

• A. 100ml 10% solution, 100ml water
• B. 150ml 10% solution, 50ml water
• C. 160ml 10% solution, 40ml water
• D. 200ml 10% solution, 0ml water

Correct answer: B

Rationale: Rationale: 1. Let x be the volume of the 10% solution needed and y be the volume of water needed. 2. The total volume of the final solution is 200ml, so x + y = 200. 3. The concentration of the final solution is 5%, so the amount of salt in the final solution is 0.05 * 200 = 10g. 4. The amount of salt in the 10% solution is 0.1x, and the amount of salt in the water is 0, so the total amount of salt in the final solution is 0.1x. 5. Since the total amount of salt in the final solution is 10g, we have 0.1x = 10. 6. Solving for x, we get x = 100ml. 7. Substituting x =

2. Rebecca is able to paint 12 pickets on her picket fence in an hour. Her fence is 72 feet long, with 2 pickets per foot. How long will it take her to paint the fence?

• A. 2.4 hours
• B. 6 hours
• C. 12 hours
• D. 16.4 hours

Correct answer: B

Rationale: Rebecca can paint 12 pickets in 1 hour, which means she can paint 12 * 2 = 24 pickets in an hour. Since the fence is 72 feet long with 2 pickets per foot, she needs to paint a total of 72 * 2 = 144 pickets. If she paints 24 pickets per hour, it will take her 144 / 24 = 6 hours to paint the entire fence. Choice A (2.4 hours) is incorrect because it does not consider the total number of pickets on the fence. Choice C (12 hours) is incorrect as it overestimates the time needed based on her painting rate. Choice D (16.4 hours) is incorrect as it miscalculates the time required to paint the entire fence.

3. A solution is 60% alcohol. If 200ml of the solution is used, how much pure alcohol is present?

• A. 100ml
• B. 120ml
• C. 140ml
• D. 160ml

Correct answer: B

Rationale: If the solution is 60% alcohol, it means that 60% of the solution is alcohol. Therefore, in 200ml of the solution, the amount of alcohol present is: 200ml * 60% = 200ml * 0.60 = 120ml. So, when 200ml of the solution is used, there are 120ml of pure alcohol present. Choice A, 100ml, is incorrect because it does not account for the correct percentage of alcohol in the solution. Choice C, 140ml, and Choice D, 160ml, are incorrect as they overestimate the amount of pure alcohol present in the solution.

4. Evaluate the following expression: -x + y + xy, when x = 4 and y = 2.

• A. 2
• B. 6
• C. 12
• D. 8

Correct answer: B

Rationale: To evaluate the expression, substitute x = 4 and y = 2 into the expression: -4 + 2 + 4*2. Calculate each term: -4 + 2 = -2, then 4*2 = 8. Adding these results gives -2 + 8 = 6. Therefore, the correct answer is 6. Choice A (2) is incorrect as it does not consider all terms in the expression. Choice C (12) is incorrect as it miscalculates the result by failing to account for the negative sign. Choice D (8) is incorrect as it doesn't consider the negative value of the first term in the expression.

5. A plan for a house is drawn on a 1:40 scale. If the length of the living room on the plan measures 5 inches, what is the actual length of the built living room?

• A. 45 feet
• B. 25 feet
• C. 15 feet
• D. 12 feet

Correct answer: C

Rationale: Since the scale of the plan is 1:40, this means that 1 inch on the plan represents 40 inches in reality. Therefore, the actual length of the living room can be calculated as 5 inches on the plan multiplied by the scale factor of 40, which equals 200 inches. Converting 200 inches to feet gives us 15 feet as the actual length of the built living room. Choice A (45 feet) is incorrect because it miscalculates the conversion from inches to feet. Choice B (25 feet) is incorrect as it does not consider the scale factor provided. Choice D (12 feet) is incorrect as it does not apply the correct scale factor to convert the plan's measurements to reality.

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