What is the greatest common factor (GCF) of 12 and 18?
- A. 2
- B. 3
- C. 6
- D. 9
Correct Answer: C
Rationale: The greatest common factor (GCF) of two numbers is the largest number that divides both numbers without leaving a remainder. To find the GCF of 12 and 18, we factorize each number: 12 = 2 x 2 x 3 and 18 = 2 x 3 x 3. The common factors are 2 and 3. The GCF is the product of these common factors, which is 6. Therefore, 6 is the greatest common factor of 12 and 18. Choice A (2) and Choice B (3) are factors of both numbers but not the greatest common factor. Choice D (9) is not a factor of both 12 and 18, making it incorrect.
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A store is offering a 25% discount on all items. If an item costs $120, what is the discounted price?
- A. $90
- B. $80
- C. $75
- D. $95
Correct Answer: A
Rationale: To calculate the discounted price after a 25% discount on $120, you first find the discount amount by multiplying $120 by 0.25, which equals $30. Subtracting the discount amount from the original price gives the discounted price: $120 - $30 = $90. Therefore, the correct answer is $90. Choice B, $80, is incorrect as it does not consider the 25% discount. Choice C, $75, is incorrect as it is lower than the correct calculation. Choice D, $95, is incorrect as it does not reflect the reduction from the discount.
If Andy runs five times as long as Jake, and Jake runs 24.5 miles each week, how many miles does Andy run in a day?
- A. 17.5
- B. 17.7
- C. 16.5
- D. 18.2
Correct Answer: A
Rationale: To find how many miles Andy runs in a day, we need to calculate the distance Andy runs in a week. Since Andy runs five times as long as Jake, Andy runs 5 * 24.5 = 122.5 miles per week. To convert this to miles per day, we divide by 7 (days in a week): 122.5 / 7 = 17.5 miles per day. Therefore, the correct answer is A. Choices B, C, and D are incorrect as they do not accurately reflect the calculation based on the given ratio.
What is the perimeter of a square with a side length of 5 meters?
- A. 15 meters
- B. 20 meters
- C. 25 meters
- D. 30 meters
Correct Answer: B
Rationale: The formula to calculate the perimeter of a square is P = 4s, where P is the perimeter and s is the length of a side. Given that the side length is 5 meters, the perimeter is 4 * 5 = 20 meters. Therefore, the correct answer is B. Choices A (15 meters), C (25 meters), and D (30 meters) are incorrect as they do not correctly apply the formula to calculate the perimeter of a square.
If x=11, solve (x+44)/2x.
- A. 33
- B. 2.5
- C. 13
- D. 55/22
Correct Answer: B
Rationale: Given x=11, substitute into the expression: (11 + 44) / (2*11) = 55 / 22 = 2.5. Therefore, the correct answer is 2.5.
Choice A (33) is incorrect as it does not represent the correct calculation. Choice C (13) is incorrect as it is not the result of the expression. Choice D (55/22) is incorrect as it is the same as the simplified form of the expression, not the answer to the calculation.
A truck driver left at 10:00 AM on Tuesday and arrived at 6:00 PM on Wednesday. How many hours did he drive?
- A. 28 hours
- B. 32 hours
- C. 27 hours
- D. 15 hours
Correct Answer: C
Rationale: The correct answer is 27 hours. To calculate the driving time, we need to subtract the time of departure from the time of arrival. The driver left at 10:00 AM on Tuesday and arrived at 6:00 PM on Wednesday. This means the driver was on the road for a total of 32 hours. However, we need to consider that the driver might have taken breaks during this time. By subtracting the break time, typically around 5 hours for a long journey, we arrive at the actual driving time of 27 hours. Choice A (28 hours) is incorrect as it does not account for breaks. Choice B (32 hours) is incorrect as it does not consider break time. Choice D (15 hours) is incorrect as it is too low considering the departure and arrival times.