Nokea
A circle has an area of 121π in². Which of the following is the circumference of the circle in terms of pi (π)?
- A. 11π in
- B. 22π in
- C. 44π in
- D. 5.5π in
Correct Answer: B
Rationale: To find the circumference of the circle, we first need to determine the radius. Given that the area of the circle is 121π in², we use the formula for the area of a circle (A = πr²) to find the radius squared. So, r² = 121, which means the radius (r) is 11 in. The circumference of a circle is calculated using the formula 2πr. Substituting the radius value of 11 in, we get 2π(11) = 22π in. Therefore, the correct answer is 22π in. Choice A (11π in), Choice C (44π in), and Choice D (5.5π in) are incorrect because they do not correctly calculate the circumference based on the given area of the circle.
You may also like to solve these questions
Which of the following is the decimal form of 87.5%?
- A. 875
- B. 8,750
- C. 0.875
- D. 8.75
Correct Answer: C
Rationale: To convert a percentage to a decimal, you move the decimal point two places to the left. Therefore, 87.5% as a decimal is 0.875. Choice A (875) is incorrect as it represents the percentage without converting to a decimal. Choice B (8,750) is incorrect as it represents the percentage in whole numbers without decimal conversion. Choice D (8.75) is incorrect as it represents 875% instead of 87.5%.
Jacob has $100. She spends 87% of the money. She then invests the remaining amount and earns a profit of 75%. How much money does she now have?
- A. $13.00
- B. $87.00
- C. $22.75
- D. $9.75
Correct Answer: C
Rationale: Jacob spends 87% of $100, which is $87, leaving her with $13. When she invests the remaining $13 and earns a 75% profit, she gains an additional $9.75. Thus, the total amount she now has is $13 (remaining amount) + $9.75 (profit) = $22.75. Choice A is incorrect as it reflects the remaining amount before investing and earning a profit. Choice B is incorrect as it does not account for the profit earned from the investment. Choice D is incorrect as it only considers the profit amount, not the total sum.
Elevation above sea level and temperature are negatively correlated variables. Which of the following statements describes the relationship between the variables?
- A. As elevation decreases, temperature remains the same
- B. As elevation decreases, temperature decreases
- C. As elevation increases, temperature decreases
- D. As elevation increases, temperature increases
Correct Answer: C
Rationale: The correct answer is C: 'As elevation increases, temperature decreases.' In a negative correlation, the variables move in opposite directions. As elevation rises, temperature tends to decrease. Choice A is incorrect because a negative correlation implies that as one variable increases, the other decreases. Choices B and D are incorrect because they suggest that temperature either remains the same or increases as elevation decreases or increases, which is inconsistent with a negative correlation.
Which of the following values is the greatest?
- A. 2/11
- B. 5.4
- C. 13/3
- D. 6.25
Correct Answer: D
Rationale: To determine the greatest value among the given options, convert the fractions to decimal form. 2/11 is approximately 0.1818, 5.4 is a decimal itself, 13/3 is approximately 4.333, and 6.25 is a decimal. Comparing these values, 6.25 is the largest among them. Therefore, option D, 6.25, is the correct answer. Choices A, B, and C are smaller values compared to 6.25, making them incorrect answers.
Which of the following is the most likely weight of a pencil?
- A. 25 kg
- B. 25 cm
- C. 25 mg
- D. 25 g
Correct Answer: D
Rationale: The correct answer is 25 g. Pencils are usually lightweight, and their weight is measured in grams. 25 kg (choice A) is too heavy for a pencil. 25 cm (choice B) is a unit of length, not weight. 25 mg (choice C) is too light for a pencil, as pencils typically weigh more than milligrams.