Nokea
A scientist is trying to determine how much poison will kill a rat the fastest. Which of the following statements is an example of an appropriate hypothesis?
- A. Rats that are given lots of poison seem to die quickly.
- B. Does the amount of poison affect how quickly the rat dies?
- C. The more poison a rat is given, the quicker it will die.
- D. Poison is fatal to rats.
Correct Answer: C
Rationale: A valid hypothesis must be a testable statement that predicts a relationship between variables. Option C is the only statement that presents a clear cause-and-effect relationship between the amount of poison given and the time it takes for the rat to die. Option A is descriptive without predicting an outcome, option B is a question rather than a statement, and option D is a general fact about poison and rats, lacking a specific hypothesis for testing.
You may also like to solve these questions
If ð‘› = 8, then n is between which of the following ranges?
- A. 5 and 7
- B. 7 and 9
- C. 9 and 11
- D. 3 and 5
Correct Answer: B
Rationale: To find the range where n lies when n = 8, we consider numbers greater and lesser than 8. The range would be between 7 and 9, not 9 and 11 as stated in the original rationale. Option A (5 and 7) and Option D (3 and 5) are lower ranges, while Option C (9 and 11) exceeds the upper limit.
Jessica buys 10 cans of paint. Red paint costs $1 per can, and blue paint costs $2 per can. In total, she spends $16. How many red cans did she buy?
- A. 2
- B. 3
- C. 4
- D. 5
Correct Answer: C
Rationale: Let r be the number of red cans and b be the number of blue cans. The total cans equation is r + b = 10. The total cost equation is r + 2b = 16. By solving these equations simultaneously, we find r = 4. Therefore, Jessica bought 4 red cans. Choice A, 2 red cans, is incorrect because it does not satisfy the total cans or total cost condition. Choices B and D are also incorrect as they do not fulfill both conditions simultaneously.
Which number is larger, 0.5 or 1/3?
- A. 0.5
- B. 1/3
- C. They are equal
- D. Cannot be determined
Correct Answer: A
Rationale: To compare 0.5 and 1/3, we can convert 0.5 to a fraction, which is 1/2. When comparing 1/2 and 1/3, we find that 1/2 is greater than 1/3. Therefore, 0.5 is larger than 1/3. Choice B is incorrect as 1/3 is smaller. Choice C is incorrect as the numbers are not equal. Choice D is incorrect as a clear comparison can be made.
Which of the following is NOT a way to write 40 percent of N?
- A. 0.4N
- B. N/40
- C. 2/5 N
- D. 40N/100
Correct Answer: B
Rationale: The correct answer is B: N/40. To find 40% of N, you multiply N by 0.4, so 0.4N is the correct representation. Choice B, N/40, is incorrect because dividing N by 40 does not give you 40% of N. Choice C, 2/5 N, is equivalent to 40% of N since 2/5 is the same as 40% when simplified. Choice D, 40N/100, is also correct since 40% can be represented as 40/100, which simplifies to 0.4, making 40N/100 another valid way to write 40% of N.
What is the mode of the set of numbers {4, 4, 5, 7, 8}?
- A. 4
- B. 5
- C. 7
- D. 8
Correct Answer: A
Rationale: The mode of a set of numbers is the value that appears most frequently. In the given set {4, 4, 5, 7, 8}, the number 4 appears twice, which is more frequent than any other number. Therefore, the mode of this set is 4. Choice B, 5, is incorrect as it only appears once in the set. Choices C and D, 7 and 8 respectively, also appear only once each, making them less frequent than the number 4.