Nokea
A circular swimming pool has a circumference of 49 feet. What is the diameter of the pool?
- A. 15.6 feet
- B. 17.8 feet
- C. 49 feet
- D. 153.9 feet
Correct Answer: A
Rationale: The formula for the circumference of a circle is C = πd, where C is the circumference and d is the diameter. Given C = 49 feet, we can rearrange the formula to solve for d: 49 feet = πd. To find the diameter, we divide both sides by π, giving us d = 49 feet / π ≈ 15.6 feet. Therefore, the diameter of the swimming pool is approximately 15.6 feet. Choices B, C, and D are incorrect because they do not align with the calculation based on the formula for the circumference of a circle.
You may also like to solve these questions
x · 7 = x − 36. Solve the equation. Which of the following is correct?
- A. x = 6
- B. x = 42
- C. x = 4
- D. x = 252
Correct Answer: B
Rationale: To solve the equation x · 7 = x − 36, start by multiplying both sides by 7 to get 7(x · 7) = 7(x − 36), which simplifies to x = 7x − 252. Next, subtract 7x from both sides to get -6x = -252. Finally, divide both sides by -6 to solve for x, which results in x = 42. Therefore, the correct answer is x = 42. Choice A (x = 6), Choice C (x = 4), and Choice D (x = 252) are incorrect as they do not align with the correct solution derived from the equation.
Simplify the expression. Which of the following is the value of x? (5(4x - 5) = (3/2)(2x - 6))
- A. −(2/7)
- B. −(4/17)
- C. (16/17)
- D. (8/7)
Correct Answer: C
Rationale: To solve the given proportion 5(4x - 5) = (3/2)(2x - 6), first distribute to get 20x - 25 = 3x - 9. Then, simplify the linear equation by isolating x: 20x - 3x = 25 - 9, which leads to 17x = 16. Finally, solving for x gives x = 16/17. Choice A is incorrect as it does not match the calculated value of x. Choice B is incorrect as it does not correspond to the correct solution for x. Choice D is incorrect as it does not align with the accurate value of x obtained from solving the equation.
Anna is buying fruit at the farmers' market. She selects 1.2 kilograms of apples, 800 grams of bananas, and 300 grams of strawberries. The farmer charges her a flat rate of $4 per kilogram. What is the total cost of her produce?
- A. $4.40
- B. $5.24
- C. $9.20
- D. $48.80
Correct Answer: C
Rationale: To calculate the total cost, convert all weights to kilograms. 800 grams = 0.8 kilograms; 300 grams = 0.3 kilograms. Add up the weights: 1.2 kg + 0.8 kg + 0.3 kg = 2.3 kg. Multiply the total weight by the cost per kilogram: 2.3 kg $4/kg = $9.20. Therefore, the total cost of her produce is $9.20. Choice A, $4.40, is incorrect as it does not account for the total weight of all the fruits. Choice B, $5.24, is incorrect as it does not accurately calculate the total cost based on the given weights and price per kilogram. Choice D, $48.80, is incorrect as it is significantly higher than the correct total cost and suggests an incorrect calculation method.
What is the result of the expression 102 - 7(3 - 4) - 25? Which of the following is correct?
- A. -12
- B. 2
- C. 68
- D. 82
Correct Answer: D
Rationale: To simplify the expression, we follow the order of operations (PEMDAS): Parentheses, Exponents, Multiplication and Division (from left to right), Addition and Subtraction (from left to right). First, solve inside the parentheses: 3 - 4 = -1. Then, multiply -1 by 7: -1 * 7 = -7. Now, substitute these values back into the expression: 102 - (-7) - 25 = 102 + 7 - 25 = 109 - 25 = 84. Therefore, the correct answer is 84. Choices A, B, and C are incorrect as they do not represent the correct simplification of the given expression.
Which of the following is the y-intercept of the line whose equation is 7y − 42x + 7 = 0?
- A. (1/6, 0)
- B. (6, 0)
- C. (0, −1)
- D. (−1, 0)
Correct Answer: C
Rationale: To find the y-intercept, set x = 0 in the equation 7y − 42x + 7 = 0. This simplifies to 7y - 42(0) + 7 = 0, which gives 7y = -7. Solving for y, we get y = -1. Therefore, the y-intercept is where x = 0, so the correct answer is (0, -1).
Choice A (1/6, 0) is incorrect as it does not satisfy the given equation when x = 0. Choice B (6, 0) is incorrect as it represents the x-intercept. Choice D (-1, 0) is incorrect as it does not correspond to the y-intercept of the given equation.