a patient is prescribed 500 mg of medication but the available tablets are 250 mg each how many tablets should be given

HESI A2

HESI A2 Math

1. A patient is prescribed 500 mg of medication, but the available tablets are 250 mg each. How many tablets should be given?

A. 3 tablets
B. 2 tablets
C. 4 tablets
D. 5 tablets

Correct answer: B

Rationale: To find out how many tablets of 250 mg are needed to reach a total of 500 mg, you divide the total prescribed dosage by the dosage per tablet. In this case, 500 mg / 250 mg per tablet = 2 tablets. Therefore, the correct answer is 2 tablets. Choice A (3 tablets) is incorrect because it would exceed the prescribed dosage. Choices C (4 tablets) and D (5 tablets) are incorrect as they would also provide more medication than needed.

2. What is the result of adding 12 1/21 and 3 1/3?

A. 15 8/21
B. 16 5/24
C. 15
D. 14

Correct answer: A

Rationale: To add 12 1/21 and 3 1/3, first add the whole numbers: 12 + 3 = 15. Then, add the fractions: 1/21 + 1/3. To find a common denominator, multiply 21 by 3 to get 63. Convert 1/21 to an equivalent fraction with a denominator of 63 by multiplying the numerator and denominator by 3, resulting in 3/63. Now add 3/63 (equivalent to 1/21) and 21/63 (equivalent to 1/3) to get 24/63. Simplifying 24/63 gives 8/21. Therefore, the sum is 15 8/21. Choices B, C, and D are incorrect because they do not result from the correct addition of the given numbers and fractions.

3. A medication order is for 250 micrograms of a drug to be administered subcutaneously. The available syringe measures in milliliters. How many milliliters should the healthcare professional draw up?

A. 0.00025 milliliters
B. 0.0025 milliliters
C. 0.025 milliliters
D. 0.25 milliliters

Correct answer: D

Rationale: 1 milliliter (mL) is equal to 1000 micrograms (mcg). Therefore, to find out how many milliliters are needed for 250 micrograms: 250 mcg ÷ 1000 = 0.25 mL. So, the healthcare professional should draw up 0.25 milliliters of the drug to administer 250 micrograms subcutaneously. Choice A, 0.00025 milliliters, is incorrect as it is too small a volume for the required dosage. Choice B, 0.0025 milliliters, is also too small. Choice C, 0.025 milliliters, is 100 times greater than the correct answer of 0.25 milliliters. Therefore, the correct answer is 0.25 milliliters.

4. What is the result of the expression 47/57 + 65/75?

A. 1 23/35
B. 2 1/3
C. 1 2/3
D. 1 5/6

Correct answer: A

Rationale: To add fractions, you need a common denominator. In this case, the common denominator is 57 * 75 = 4275. So, (47*75 + 65*57) / 4275 = (3525 + 3705) / 4275 = 7230 / 4275. Simplifying this fraction gives 1 23/35. Choice B: 2 1/3 is incorrect as the correct result is not a mixed number. Choice C: 1 2/3 is incorrect as it does not match the simplified result of the expression. Choice D: 1 5/6 is incorrect as it is a different value from the correct result obtained by adding the fractions.