Number System If x + y = 61 and xy = 888, What is the value of x²+ y² ? 1945 1955 1965 1975 1945 1955 1965 1975 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Because (x + y)² = x² + y² + 2xy∴ x² + y² = (x + y)² - 2xy∴ x² + y² = (61)² - 2 x 888= 3721 - 1776 = 1945
Number System A two-digit number is such that the product of the digits is 8. When 18 is added to the number, then the digits are reversed. The number is: 81 18 42 24 81 18 42 24 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the ten's and unit's digit be x and 8/x respectively. Then, (10x + 8/x) + 18 = 10 * 8/x + x 9x2 + 18x - 72 = 0 x2 + 2x - 8 = 0 (x + 4)(x - 2) = 0 x = 2 So, ten's digit = 2 and unit's digit = 4. Hence, required number = 24.
Number System In how many different ways can the letters of the word CORPORATION be arranged ? None of these 1326400 2326400 3326400 None of these 1326400 2326400 3326400 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP CORPORATION = 11 letters 'O' comes thrice,'R' twice.∴ total no. of ways = 111/3121 = 3326400
Number System The difference between 8% of a number and 3% of the same number is 39. What is 2.8% of that number ? 25.84 21.84 24.84 27.84 25.84 21.84 24.84 27.84 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the number be x.∴ x(8 - 3)% = 39x = 3900/5 = 780∴ 2.8% of 780= 780 x 2.8/100 = 21.84
Number System 84 * 29 + 365 = ? 2436 - 2071 - 2801 2801 2436 - 2071 - 2801 2801 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP - 84 * (30 - 1) + 365= - (84 * 30) + 84 + 365= - 2520 + 449 = - 2071
Number System The product of two consecutive odd numbers is 4623. What is the product of the next two consecutive odd numbers ? 5183 8795 7745 6782 5183 8795 7745 6782 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP √4623 = 6767 x 69 = 4623∴ Required product = 71 x 73 = 5183
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