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The order of operations (PEMDAS) dictates the sequence for evaluating mathematical expressions. If a = 2 and b = -3, what is the value of 3a^2 - 2ab + b^2?
- A. -3
- C. 33
- D. 15
Correct Answer: C
Rationale: Given expression: 3a^2 - 2ab + b^2. Substitute the values of a and b: 3(2)^2 - 2(2)(-3) + (-3)^2 = 3(4) + 12 + 9 = 12 + 12 + 9 = 24 + 9 = 33. Therefore, the value of the expression is 33, which corresponds to option C. Options A, B, and D are incorrect as they do not accurately evaluate the expression with the given values of a and b.
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If his distribution cost is $10, what will be his profit?
- A. $10.40
- B. $19.60
- C. $14.90
- D. $23.40
Correct Answer: B
Rationale: To calculate profit, we subtract the total distribution cost from the revenue. Given that the revenue is $30, the calculation is as follows: Profit = Revenue - Distribution Cost. Therefore, Profit = $30 - $10 = $20. Hence, the profit will be $19.60. Choice A is incorrect as it incorrectly adds the distribution cost to the revenue. Choice C is incorrect as it does not consider the distribution cost. Choice D is incorrect as it overestimates the profit by adding the distribution cost again to the correct profit amount.
How many yards are in a mile?
- A. 1,760
- B. 1,700
- C. 1,800
- D. 1,750
Correct Answer: A
Rationale: The correct answer is A: 1,760. According to the standard distance conversion, there are 1,760 yards in a mile. This conversion is widely accepted and used in various fields. Choice B, 1,700, is incorrect as it does not correspond to the standard conversion. Choice C, 1,800, represents a different value and is therefore incorrect. Choice D, 1,750, is not the accurate conversion for yards in a mile and is incorrect.
In the time required to serve 43 customers, a server breaks 2 glasses and slips 5 times. The next day, the same server breaks 10 glasses. How many customers did she serve?
- A. 25
- B. 43
- C. 86
- D. 215
Correct Answer: C
Rationale: In the first scenario, for 43 customers served, the server broke 2 glasses and slipped 5 times. This means for each customer served, the server broke 2/43 glasses and slipped 5/43 times. The information about breaking 10 glasses the next day is irrelevant to the number of customers served. Therefore, to find out the total number of customers served, we calculate 43 customers * (2 glasses/customer + 5 slips/customer) = 86. Choice A, 25, is incorrect as it does not consider the total number of glasses broken or slips. Choice B, 43, is incorrect because it only considers the initial number of customers. Choice D, 215, is incorrect as it miscalculates the relationship between customers, glasses broken, and slips.
Add: 1.332 + 0.067
- A. 1.399
- B. 1.4
- C. 1.402
- D. 1.5
Correct Answer: A
Rationale: To find the sum of 1.332 and 0.067, add the two numbers correctly: 1.332 + 0.067 = 1.399. Therefore, the correct answer is A. Choice B (1.4) is incorrect because it rounds down the sum, not considering the precise value. Choice C (1.402) is incorrect as it results from adding 1.332 and 0.070 instead of 0.067. Choice D (1.5) is not the correct sum of the given numbers.
What is 72 inches converted to feet?
- A. 12 feet
- B. 6 feet
- C. 4 feet
- D. 17 feet
Correct Answer: B
Rationale: To convert inches to feet, you divide the number of inches by 12 since there are 12 inches in a foot. Therefore, 72 inches divided by 12 equals 6 feet. The correct answer is 6 feet. Choice A, 12 feet, is incorrect as it is the result if we were converting 144 inches. Choice C, 4 feet, and Choice D, 17 feet, are incorrect conversions and do not correspond to the given measurement of 72 inches.