twenty is 40 of what number

ATI TEAS 7

TEAS Math Practice Test

1. What number is 20 equal to 40% of?

A. 50
B. 8
C. 200
D. 5000

Correct answer: A

Rationale: To find the number that 20 is equal to 40% of, you can set up the equation: 20 = 0.4 * x, where x is the unknown number. To solve for x, divide both sides of the equation by 0.4. This gives x = 20 / 0.4 = 50. Therefore, 20 is 40% of 50. Choice B, 8, is incorrect because 20 is not equal to 40% of 8. Choice C, 200, is incorrect because 20 is not equal to 40% of 200. Choice D, 5000, is incorrect because 20 is not equal to 40% of 5000. The correct answer is 50.

2. Which of the following is NOT a way to write 40 percent of N?

A. 0.4N
B. N/40
C. 2/5 N
D. 40N/100

Correct answer: B

Rationale: The correct answer is B: N/40. To find 40% of N, you multiply N by 0.4, so 0.4N is the correct representation. Choice B, N/40, is incorrect because dividing N by 40 does not give you 40% of N. Choice C, 2/5 N, is equivalent to 40% of N since 2/5 is the same as 40% when simplified. Choice D, 40N/100, is also correct since 40% can be represented as 40/100, which simplifies to 0.4, making 40N/100 another valid way to write 40% of N.

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. Which statement best describes the rate of change?

A. Every day, the snow melts 10 centimeters.
B. Every day, the snow melts 5 centimeters.
C. Every day, the snow increases by 10 centimeters.
D. Every day, the snow increases by 5 centimeters.

Correct answer: B

Rationale: The rate of change refers to how one quantity changes concerning another quantity. In this scenario, the rate of change is the amount of snow melting per day, which is 5 centimeters. This is determined by the slope of the graph, indicating a decrease in snow depth. Choices C and D incorrectly describe an increase in snow depth, while choice A exaggerates the rate of snow melting compared to the actual value of 5 centimeters per day.

5. Susan bought a dress for $69.99, shoes for $39.99, and accessories for $34.67. What was the total cost of her outfit?

A. 139.65
B. 144.65
C. 145.55
D. 144.65

Correct answer: B

Rationale: To find the total cost of Susan's outfit, you need to add the prices of the dress, shoes, and accessories together. $69.99 + $39.99 + $34.67 = $144.65. Therefore, the correct total cost of her outfit is $144.65. Choice A ($139.65) is incorrect as it does not account for the full cost of all items. Choice C ($145.55) is incorrect as it includes an extra amount not part of the given prices. Choice D ($144.65) is incorrect due to a duplication of the correct answer.