A decorative globe has a diameter of 25cm. What is its total surface area?
- A. 1570 sq cm
- B. 1963 sq cm
- C. 2513 sq cm
- D. 3142 sq cm
Correct Answer: B
Rationale: To find the total surface area of a sphere, you can use the formula: 4 * π * (radius)^2, where the radius is half the diameter. Given that the diameter is 25cm, the radius is half of that, which is 12.5cm. Substitute this value into the formula: 4 * π * (12.5cm)^2 ≈ 1963 sq cm. Therefore, the total surface area of the decorative globe is approximately 1963 sq cm. Choices A, C, and D are incorrect as they do not correspond to the correct calculation.
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The plane is due to land at 6:20 P.M. What would that be in military time?
- A. 620
- B. 1820
- C. 6020
- D. 6200
Correct Answer: B
Rationale: In military time, the afternoon and evening hours are represented by adding 12 to the standard time. Therefore, 6:20 P.M. would be equivalent to 18:20 in military time. To convert from P.M. to military time, simply add 12 hours to the given time. Choice A, '620,' is incorrect because it does not account for converting to military time. Choice C, '6020,' is incorrect as military time uses a 24-hour clock format, and the hour digit should not exceed 23. Choice D, '6200,' is incorrect as it does not follow the military time format where the hour part ranges from 00 to 23.
Convert this military time to regular time: 1010 hours.
- A. 10:10 A.M.
- B. 10:10 P.M.
- C. 1:01 A.M.
- D. 1:01 P.M.
Correct Answer: A
Rationale: To convert military time to regular time, we can drop the first two digits if they are less than 12. 1010 hours can be converted to 10:10 A.M. because it is before noon (12:00 P.M.). Military time operates on a 24-hour clock system, with 0000 hours indicating midnight and 1200 hours representing noon. Therefore, in this case, 1010 corresponds to 10:10 A.M. Choice B (10:10 P.M.) is incorrect as 1010 hours is in the morning, not the evening. Choices C (1:01 A.M.) and D (1:01 P.M.) are incorrect as they do not match the given military time of 1010 hours.
For his daily commute, Paul drives about 115 miles round trip. If he fills up his gas tank with 9 gallons every other day, about how many miles per gallon is his car averaging?
- A. 12.8
- B. 23
- C. 25.6
- D. 57.5
Correct Answer: C
Rationale: To find the miles per gallon Paul's car is averaging, we first need to determine the miles he drives on 9 gallons of gas. Since he drives about 115 miles round trip daily, he covers approximately 115/2 = 57.5 miles one way. If he fills up his gas tank with 9 gallons every other day, he covers 115 miles every 2 days. This means his car is averaging around 57.5 miles per 9 gallons, which equals approximately 6.38 miles per gallon. As he uses 9 gallons every other day, his car averages about 6.38 * 2 = 12.76 miles per gallon. Among the given options, the closest value to this calculation is option C, 25.6 miles per gallon. Choice A is incorrect because it does not accurately reflect the mileage per gallon calculation. Choice B is incorrect as it is not the closest to the calculated value. Choice D is incorrect as it is significantly higher than the calculated mileage per gallon.
If Jolene averages 5 miles for every 30 minutes of biking, how far will she bike in 2 hours?
- A. 10 miles
- B. 15 miles
- C. 20 miles
- D. 30 miles
Correct Answer: C
Rationale: If Jolene bikes 5 miles for every 30 minutes, it means she bikes 10 miles in one hour (twice the 30-minute interval). Therefore, in 2 hours, she will cover double the distance she bikes in one hour, which equals 20 miles (10 miles per hour x 2 hours = 20 miles). This makes Choice C, '20 miles,' the correct answer. Choices A, B, and D are incorrect as they do not account for the correct doubling of the hourly distance when calculating the total distance biked in 2 hours.
What is the volume of water needed to fill a rectangular swimming pool with dimensions 10 meters by 5 meters and a depth of 2 meters?
- A. 50 cu m
- B. 100 cu m
- C. 150 cu m
- D. 200 cu m
Correct Answer: B
Rationale: To find the volume of the rectangular swimming pool, you need to multiply the length by the width by the depth. Volume = Length x Width x Depth. Therefore, Volume = 10m x 5m x 2m = 100 cubic meters. This means it takes 100 cubic meters of water to fill the pool. Choices A, C, and D are incorrect as they do not correctly calculate the volume based on the provided dimensions.