A bag contains 5 red marbles and 7 blue marbles. If you draw a marble without looking, what is the probability it will be red?
- A. 1/4
- B. 1/3
- C. 1/2
- D. 2/3
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.
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If the outside temperature is currently 15 degrees on the Celsius scale, what is the approximate temperature on the Fahrenheit scale?
- A. 59°F
- B. 61°F
- C. 63.5°F
- D. 65.2°F
Correct Answer: A
Rationale: To convert Celsius to Fahrenheit, you can use the formula: (°C 9/5) + 32 = °F. Substituting 15°C into the formula gives us (15 9/5) + 32 = 59°F. Therefore, the approximate temperature on the Fahrenheit scale for 15 degrees Celsius is 59 degrees Fahrenheit. Choice B, C, and D are incorrect as they do not align with the correct conversion formula and calculation.
How many kilometers are there in 12 miles?
- A. 7.5 kilometers
- B. 13.2 kilometers
- C. 19.2 kilometers
- D. 22 kilometers
Correct Answer: C
Rationale: To convert miles to kilometers, you can use the conversion factor of 1 mile is equal to 1.609 kilometers. Therefore, to find the number of kilometers in 12 miles, you can multiply 12 miles by 1.609 to get 19.2 kilometers. The correct answer is 19.2 kilometers, making choice C the correct option. Choice A (7.5 kilometers) is incorrect because it represents half the correct conversion. Choice B (13.2 kilometers) is incorrect as it does not apply the correct conversion factor. Choice D (22 kilometers) is incorrect and represents an incorrect conversion calculation.
Which numeric system was a base 20 system?
- A. Mayan
- B. Babylonian
- C. Roman
- D. Arabic
Correct Answer: A
Rationale: The Mayan numeric system was a base 20 system, known as vigesimal, as it used base 20 numerals. This system was unique and employed a combination of symbols and positional notation to represent numbers. The Babylonian system was a base 60 system, Roman numerals were based on combinations of letters, and Arabic numerals are in base 10, making choices B, C, and D incorrect.
A patient's oxygen flow rate is set at 4 liters per minute. How many cubic centimeters of oxygen are delivered per minute?
- A. 400 cubic centimeters
- B. 4,000 cubic centimeters
- C. 40,000 cubic centimeters
- D. 400,000 cubic centimeters
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.
What time is 6:30 A.M. in military time?
- A. 0630
- B. 6030
- C. 1503
- D. 1530
Correct Answer: A
Rationale: Military time uses a 24-hour clock format where the hours range from 00 to 23. In this format, 6:30 A.M. is expressed as 0630. Choice B (6030) and Choice C (1503) are incorrect as they do not follow the 24-hour clock format. Choice D (1530) represents 3:30 P.M., not 6:30 A.M.