Add 2/3 + 4/9.
- A. 8/15
- B. 1
- C. 10/9
- D. 1/2
Correct Answer: C
Rationale: To add the fractions, first find a common denominator. The least common denominator between 3 and 9 is 9.
Convert 2/3 to 6/9 then add 6/9 + 4/9:
= 10/9
You may also like to solve these questions
Solve for x: 3(x - 4) = 18.
- A. x = 10
- B. x = 12
- C. x = 5
- D. x = 3
Correct Answer: A
Rationale: To solve the equation, begin by distributing the 3 on the left side: 3x - 12 = 18. Next, add 12 to both sides to isolate x: 3x = 30. Finally, divide by 3 to determine the value of x: x = 10. Therefore, the correct answer is x = 10. Choice B, x = 12, is incorrect as the correct value of x is 10, not 12. Choice C, x = 5, is incorrect as it does not satisfy the equation after substitution. Choice D, x = 3, is incorrect as it does not fulfill the equation when substituted back.
Change the following percentage to a decimal: 58%
- A. 0.58
- B. 5
Correct Answer: A
Rationale: To convert a percentage to a decimal, move the decimal point two places to the left. Therefore, 58% as a decimal is 0.58. Choice B, 5, is incorrect as it does not represent the conversion of a percentage to a decimal. Choices C and D, both 0, are also incorrect as they do not reflect the correct conversion of 58% to a decimal.
A birdbath has a hemispherical bowl with a diameter of 30cm. What is its volume?
- A. 675 cu cm
- B. 1350 cu cm
- C. 2700 cu cm
- D. 4050 cu cm
Correct Answer: C
Rationale: To find the volume of a hemispherical bowl, we use half the formula for a sphere's volume: (2/3) * π * (radius)^3. Given the diameter is 30cm, the radius is half of that, which is 15cm. Substitute the radius into the formula: (2/3) * π * (15cm)^3 ≈ 2700 cu cm. Therefore, the correct volume is approximately 2700 cu cm. Choices A, B, and D are incorrect as they do not correctly calculate the volume of the hemispherical bowl.
Given 15:x=3:8, find x.
- A. x=40
- B. x=20
- C. x=30
- D. x=10
Correct Answer: A
Rationale: To find x, we set up the proportion 15:x = 3:8. Cross multiply to get 15*8 = 3*x, which simplifies to 120 = 3x. Dividing by 3 on both sides gives x = 40. Therefore, x=40 is the correct answer. Choices B, C, and D are incorrect because they do not match the correct calculation. Option B results from incorrectly dividing 15 by 3 instead of multiplying it by 8. Option C comes from dividing 15 by 3, and Option D is the result of dividing 15 by 8 instead of multiplying by 3.
The height of a building is 150 feet. If each floor of the building is 12 feet high, how many floors are in the building?
- A. 13 floors
- B. 15 floors
- C. 10 floors
- D. 18 floors
Correct Answer: A
Rationale: To determine the number of floors in the building, divide the total height of the building (150 feet) by the height of each floor (12 feet). 150 feet · 12 feet per floor = 12.5 floors. Since floors cannot be in fractions, the answer is rounded down to the nearest whole number, which is 13 floors. Therefore, the correct answer is A: 13 floors. Choice B (15 floors) is incorrect because the calculation results in 12.5 floors, which should be rounded down. Choices C (10 floors) and D (18 floors) are incorrect as they do not accurately reflect the division result and rounding down process.