which of the following is not a way to write 40 percent of n

ATI TEAS 7

TEAS Math Practice Test

1. 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.

2. Robert plans to drive 1,800 miles. His car gets 30 miles per gallon, and his tank holds 12 gallons. How many tanks of gas will he need for the trip?

A. 4 tanks
B. 5 tanks
C. 6 tanks
D. 7 tanks

Correct answer: B

Rationale: To calculate how many gallons of gas Robert needs for the 1,800-mile trip, divide the total distance by the car's mileage per gallon: 1,800 miles ÷ 30 mpg = 60 gallons. Since his tank holds 12 gallons, Robert will need 60 gallons ÷ 12 gallons per tank = 5 tanks of gas for the trip. Choice A (4 tanks), Choice C (6 tanks), and Choice D (7 tanks) are incorrect as they do not correctly calculate the number of tanks needed based on the car's mileage and tank capacity.

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 options correctly orders the numbers below from least to greatest? 235.971, 145.884, -271.906, -193.823

A. -271.906, -193.823, 145.884, 235.971
B. -271.906, 235.971, -193.823, 145.884
C. 145.884, -193.823, 235.971, -271.906
D. -193.823, -271.906, 145.884, 235.971

Correct answer: A

Rationale: To correctly order the numbers from least to greatest, we start with the smallest number, which is -271.906, followed by -193.823, 145.884, and finally 235.971. Therefore, the correct order is -271.906, -193.823, 145.884, 235.971. Choice A is correct. Choice B is incorrect as it incorrectly places 235.971 before -193.823. Choice C is incorrect as it starts with the largest number, 145.884. Choice D is incorrect as it starts with -193.823, which is not the smallest number in the list.

5. The hypotenuse (side C) of a triangle is 13 inches long. Which of the following pairs of measurements could be correct for the lengths of the other two sides of the triangle? (Note: A² + B² = C²)

A. 5 inches, 12 inches
B. 2.5 inches, 6 inches
C. 2.5 inches, 4 inches
D. 5 inches, 8 inches

Correct answer: A

Rationale: The correct answer is A. Using the Pythagorean theorem (A² + B² = C²), we substitute the values: 5² + 12² = 13². This simplifies to 25 + 144 = 169, which is true. Therefore, 5 inches and 12 inches could be the lengths of the other two sides. Choices B, C, and D do not satisfy the Pythagorean theorem, making them incorrect options.