On a floor plan drawn at a scale of 1:100, the area of a rectangular room is 50 cm². What is the actual area of the room?
- A. 500 m²
- B. 50 m²
- C. 5000 cm²
- D. 500 cm²
Correct Answer: D
Rationale: The scale of 1:100 means that 1 cm² on the floor plan represents 100 cm² in real life. To find the actual area of the room, you need to multiply the area on the floor plan by the square of the scale factor. Since the scale is 1:100, the scale factor is 100. Therefore, 50 cm² on the floor plan represents 50 * 100 = 5000 cm² in real life. Choice A (500 m²) is incorrect as it converts the area from cm² to m² without considering the scale factor. Choice B (50 m²) is incorrect as it does not account for the scale factor. Choice C (5000 cm²) is incorrect as it gives the area on the floor plan, not the actual area.
You may also like to solve these questions
If Sarah reads at an average rate of 21 pages in four nights, how long will it take her to read 140 pages?
- A. 6 nights
- B. 26 nights
- C. 8 nights
- D. 27 nights
Correct Answer: D
Rationale: If Sarah reads 21 pages in four nights, she reads at a rate of 21 / 4 = 5.25 pages per night. To read 140 pages, she would need 140 / 5.25 = 26.67 nights. Since she cannot read a fraction of a night, it would take her 27 nights to read 140 pages, making option D the correct answer. Option A is incorrect as it does not accurately reflect the calculation. Option B is incorrect as it does not consider the fractional part of the calculation, resulting in an inaccurate answer. Option C is incorrect as it does not align with the correct calculation based on Sarah's reading rate.
At the beginning of the day, Xavier has 20 apples. At lunch, he meets his sister Emma and gives her half of his apples. After lunch, he stops by his neighbor Jim's house and gives him 6 of his apples. He then uses ¾ of his remaining apples to make an apple pie for dessert at dinner. At the end of the day, how many apples does Xavier have left?
- A. 4
- B. 6
- C. 2
- D. 1
Correct Answer: D
Rationale: Xavier starts with 20 apples. He gives half of his apples to his sister Emma, which is 20 · 2 = 10 apples, leaving him with 10 apples. Then, he gives 6 apples to his neighbor Jim, leaving him with 10 - 6 = 4 apples. Using ¾ of his remaining 4 apples for the pie, he uses 3/4 x 4 = 3 apples. Therefore, he has 4 - 3 = 1 apple left at the end of the day. Choice D, 1 apple, is the correct answer. Choices A, B, and C are incorrect because Xavier ends up with 1 apple remaining, not 4, 6, or 2.
What score must Dwayne get on his next math test to maintain an overall average of at least 90?
- A. 89
- B. 98
- C. 95
- D. 100
Correct Answer: B
Rationale: To maintain an overall average of at least 90, Dwayne must aim for a score of 90 on every test. If his current average is below 90, he needs to make up for it by scoring higher on upcoming tests. Choosing 98 ensures that his overall average remains at or above 90. Choice A (89) is below the desired average of 90, so it would not be sufficient. Choices C (95) and D (100) are higher than necessary to maintain an average of at least 90.
After taking a certain antibiotic, Dr. Lee observed that 30% of all his patients developed an infection. He further noticed that 5% of those patients required hospitalization to recover from the infection. What percentage of Dr. Lee's patients were hospitalized after taking the antibiotic?
- A. 1.50%
- B. 5%
- C. 15%
- D. 30%
Correct Answer: A
Rationale: To find the percentage of Dr. Lee's patients hospitalized, you need to calculate 5% of the 30% who developed an infection. 5% of 30% is 1.5%. Therefore, 1.5% of Dr. Lee's patients were hospitalized. Choice A is correct. Choices B, C, and D are incorrect because they do not accurately reflect the calculation of the percentage of patients requiring hospitalization after taking the antibiotic.
If , then
- A. 1
- B. 2
- C. 3
- D. 4
Correct Answer: C
Rationale: If \(2x = 6\), then solving for \(x\), we have \(x = \frac{6}{2} = 3\). So, if \(x = 3\), then \(x+1 = 3+1 = 4\). Therefore, the value of \(x+1\) would be 4.