Nokea
Subtract 5/6 - 3/4.
- A. 1/12
- B. 2/24
- C. 1/2
- D. 1/8
Correct Answer: A
Rationale: To subtract fractions, find a common denominator. The common denominator for 6 and 4 is 12. So, 5/6 = 10/12 and 3/4 = 9/12. Subtracting 10/12 - 9/12 gives us 1/12 as the result. Choice A, 1/12, is the correct answer because it represents the simplified result of subtracting the fractions with the common denominator. Choices B, C, and D are incorrect because they do not reflect the correct subtraction result of 1/12 after finding the common denominator.
You may also like to solve these questions
Solve for x: x + 44 / 2x = 11.
- A. 13
- B. 33
- C. 55
- D. 2.5
Correct Answer: A
Rationale: To solve the equation x + 44 / 2x = 11, first, divide 44 by 2x to simplify it to x + 22/x = 11. Multiply through by x to clear the fraction, resulting in x^2 + 22 = 11x. Rearrange the terms to get x^2 - 11x + 22 = 0. Factor the quadratic equation to (x - 11)(x - 2) = 0. Therefore, x = 11 or x = 2. However, x cannot be 2 as it would make the denominator zero. Hence, x = 13. The correct answer is 13. Choice B (33) is incorrect as it is not a solution to the equation. Choice C (55) is incorrect as it is not a solution to the equation. Choice D (2.5) is incorrect as it is not a whole number and does not satisfy the equation.
How many kilograms are in 4,000 grams?
- A. 4 kilograms
- B. 5 kilograms
- C. 1 kilogram
- D. 2 kilograms
Correct Answer: A
Rationale: To convert grams to kilograms, divide by 1,000 because there are 1,000 grams in a kilogram. Therefore, 4,000 grams · 1,000 = 4 kilograms. Choice A is correct as it represents the correct conversion. Choice B, 5 kilograms, is incorrect because it is not the result of dividing 4,000 grams by 1,000. Choice C, 1 kilogram, is incorrect because 4,000 grams is more than 1 kilogram. Choice D, 2 kilograms, is incorrect as it is not the correct conversion from grams to kilograms.
A decorative box has a rectangular base (20cm by 15cm) and a hemispherical top with the same diameter as the base. What is the total surface area of the box (excluding the base)?
- A. 825 sq cm
- B. 1075 sq cm
- C. 1325 sq cm
- D. 1575 sq cm
Correct Answer: C
Rationale: To find the total surface area of the box excluding the base, calculate the lateral surface area of the rectangular base and the surface area of the hemisphere. The lateral surface area of the rectangular base is 2(20cm x 15cm) = 600 sq cm. The surface area of the hemisphere is 2πr^2, where r is half the diameter of the base, so r = 10cm. Thus, the surface area of the hemisphere is 2π(10cm)^2 = 200π sq cm ≈ 628.32 sq cm. Add the lateral surface area of the base and the surface area of the hemisphere: 600 sq cm + 628.32 sq cm ≈ 1228.32 sq cm. Therefore, the total surface area of the box is approximately 1228.32 sq cm, which is closest to 1325 sq cm (Choice C). Choices A, B, and D are incorrect as they do not represent the accurate calculation of the total surface area of the box.
Convert 7/8 to a decimal.
- A. 0.8
- B. 0.8
- C. 0.875
- D. 0.9
Correct Answer: C
Rationale: To convert the fraction 7/8 to a decimal, you divide the numerator (7) by the denominator (8): 7 · 8 = 0.875. Therefore, the correct decimal representation of the fraction 7/8 is 0.875. Choice A and B, which are both 0.8, are incorrect as they represent 4/5 and not 7/8. Choice D, 0.9, is also incorrect as it represents 9/10 and not 7/8.
A train travels at 80 mph for 3 hours. How far did it travel?
- A. 240 miles
- B. 160 miles
- C. 280 miles
- D. 320 miles
Correct Answer: A
Rationale: To calculate the distance traveled, you multiply the speed of the train (80 mph) by the time it traveled (3 hours): 80 mph 3 hours = 240 miles. Therefore, the correct answer is 240 miles. Choice B (160 miles) is incorrect because it results from multiplying the speed by the incorrect time. Choices C (280 miles) and D (320 miles) are incorrect as they represent calculations that do not match the given speed and time.