how do you convert f to c and c to f

ATI TEAS 7

Practice Math TEAS TEST

1. 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.

2. A lab technician took 100 hairs from a patient to conduct several tests. The technician used 1/7 of the hairs for a drug test. How many hairs were used for the drug test? (Round your answer to the nearest hundredth.)

A. 14
B. 14.2
C. 14.29
D. 14.3

Correct answer: C

Rationale: To find how many hairs were used for the drug test, you need to calculate 1/7 of 100. 1/7 of 100 is 14.2857, which rounds to 14.29 when rounded to the nearest hundredth. Therefore, 14.29 hairs were used for the drug test. Choice A is incorrect as it does not account for rounding to the nearest hundredth. Choices B and D are incorrect as they do not accurately reflect the calculated value after rounding.

3. 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.

4. How many quarts are in a gallon?

A. 1 quart
B. 2 quarts
C. 3 quarts
D. 4 quarts

Correct answer: D

Rationale: The correct answer is D, which is 4 quarts in a gallon. In the US customary system, there are 4 quarts in a gallon. Choice A is incorrect as it represents the equivalent of a quart, not a gallon. Choice B and C are incorrect as they are smaller quantities than a gallon and do not match the conversion of quarts to a gallon.

5. Which of the following describes a proportional relationship?

A. Johnathan opens a savings account with an initial deposit of $150 and deposits $125 per month
B. Bruce pays his employees $12 per hour worked during the month of December, as well as a $250 bonus
C. Alvin pays $28 per month for his phone service plus $0.07 for each long-distance minute used
D. Kevin drives 65 miles per hour

Correct answer: A

Rationale: A proportional relationship is one in which two quantities vary directly with each other. In choice A, the amount deposited per month is directly proportional to the initial deposit. The relationship can be represented as y = 125x + 150, where x is the number of months and y is the total amount in the account. Choices B and C involve additional fixed amounts or variable costs that do not maintain a constant ratio, making them non-proportional relationships. Choice D refers to a constant speed of driving, which is not a proportional relationship as it does not involve varying quantities that change in direct proportion.