The product of two numbers is 2160, and their HCF is 12. Find the numbeRs. A. (36, 60) B. (12, 180) C. (96, 25) D. (45, 48) Explanation: Let numbers = 12x,12y → xy=180 → (3,5) → (36,60).
The product of the areas of three adjacent faces of a rectangular box is equal to ____. A. Volume of the box B. Twice the volume C. Square of the volume D. Cube root of the volume Explanation: Product of face areas = (l×b)(b×h)(h×l) = (lbh)².
The probability that A speaks the truth is 3/5, and the probability that B speaks the truth is 4/7. What is the probability that both speak the truth? A. 18/35 B. 12/35 C. 17/35 D. 19/35 Explanation: Independent events → (3/5)(4/7) = 12/35? The correct answer is 12/35.
A number is selected at random from the first 50 natural numbeRs. What is the probability that it is divisible by 3 or 5? A. 21/25 B. 17/25 C. 4/25 D. 8/25 Explanation: Count the multiples and apply the inclusion-exclusion principle → 34/50 = 17/25.
The probability of a lottery ticket being a winning ticket is 0.2. If 4 tickets are bought, what is the probability of at least one win? A. 0.4869 B. 0.5904 C. 0.6234 D. 0.5834 Explanation: Probability = 1 − (0.8)⁴ = 0.5904.
The principal that amounts to Rs. 4913 in 3 years at 6¼% per annum compound interest is ____. A. Rs. 3096 B. Rs. 4076 C. Rs. 4085 D. Rs. 4096 Explanation: Using the compound interest formula, principal = 4913 / (1.0625 ) ) )³ = 4096.
The price of petrol has increased by 25%. By what percent should consumption be reduced to keep expenditure constant? A. 25% B. 30% C. 50% D. 20% Explanation: Reduction = 25/125 ×100 = 20%.
The price of an article is reduced by 25%. To restore original price, the increase needed is ____. A. 33 1/3 % B. 9 1/11 % C. 11 1/9 % D. 66 2/3 % Explanation: Same logic as above, increase must be 33 1/3%.
The price of an article is reduced by 25%. By what percent should it be increased to restore the original price? A. 33 1/3 % B. 11 1/9 % C. 9 1/11 % D. 66 2/3 % Explanation: Required increase = 25/75 ×100 = 33 1/3%.
The marked price of a VCR is Rs. 12000. After successive discounts of 15%, 10% and another discount, find the selling price. A. Rs. 8400 B. Rs. 8721 C. Rs. 8856 D. None of these Explanation: Applying successive discounts gives Rs. 8721.