HESI A2 Math Portion

Correct Answer: B

Rationale: The total number of marbles in the bag is 5 (red) + 7 (blue) = 12 marbles. The probability of drawing a red marble is the number of red marbles divided by the total number of marbles: 5/12. Simplifying 5/12 gives 1/3. Therefore, the correct probability of drawing a red marble is 1/3. Choice A (1/4) is incorrect because there are more red marbles than 1/4 of the total marbles. Choice C (1/2) is incorrect as it represents half of the total marbles. Choice D (2/3) is incorrect as it implies there are more red marbles than there actually are.

Correct Answer: B

Rationale: Olivia's Bakery gives out one extra cupcake for each dozen sold. For a special order of 180 cupcakes, there would be 180 cupcakes � 12 cupcakes per dozen = 15 dozens. Therefore, the bakery adds 15 extra cupcakes to make a 'baker's dozen' of 13 in all for each dozen, resulting in a total of 15 extra cupcakes added to the special order. The correct answer is 13 (choice B) because the bakery adds one extra cupcake to each dozen, making a 'baker's dozen' of 13.

Correct Answer: D

Rationale: When you multiply 2 by 5, the result is 10, not 13. Therefore, the correct answer is 10, which is option D. Choices A, B, and C are incorrect because they do not represent the correct product of multiplying 2 by 5.

Correct Answer: B

Rationale: 1 liter is equal to 1,000 cubic centimeters. Therefore, when the oxygen flow rate is 4 liters per minute, the calculation is 4 x 1,000 = 4,000 cubic centimeters. Hence, at a flow rate of 4 liters per minute, 4,000 cubic centimeters of oxygen are delivered per minute. Choice A, 400 cubic centimeters, is incorrect because it miscalculates the conversion from liters to cubic centimeters. Choices C and D, 40,000 cubic centimeters and 400,000 cubic centimeters, respectively, are significantly higher than the correct answer due to incorrect conversions or additional errors in calculation.

Correct Answer: C

Rationale: Let X be Bai Lin's monthly paycheck. From the given information, she puts 10% of X in savings and spends 30% on living expenses. This means she retains 60% (100% - 10% - 30%) of her paycheck, which equals $1,545. Therefore, 60% of X is $1,545. To find X, we divide $1,545 by 60% (or 0.60), which gives us X = $2,575. Hence, Bai Lin's monthly paycheck is $2,575. Therefore, the correct answer is $2,575. Choices A, B, and D are incorrect because they do not match the calculated monthly paycheck based on the given percentages and remaining amount.