Number System If x + y = 61 and xy = 888, What is the value of x²+ y² ? 1975 1955 1945 1965 1975 1955 1945 1965 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 If the difference between the squares of two consecutive numbers is 47, what is the smaller number ? 23 25 24 26 23 25 24 26 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the numbers be (x + 1) and x.Therefore, (x + 1)² - x² = 47x² + 2x + 1 - x² = 472x + 1 = 47Therefore, x = 46/2 = 23
Number System What is the sum of all even numbers from 1 to 701? 122550 122500 123850 122850 122550 122500 123850 122850 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP 700/2 = 350350 * 351 = 122850
Number System In how many different ways can be the letters of the word PENCIL be arranged among themselves ? 640 510 720 860 640 510 720 860 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Total six letters are there and hence the number of arrangements = 6! = 6 x 5 x 4 x 3 x 2 x 1 = 720
Number System The sum of four consecutive even numbers is 36. Find the sum of the squares of these numbers? 388 296 252 344 388 296 252 344 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the four numbers be x, x + 2, x + 4 and x + 6.=> x + x + 2 + x + 4 + x + 6 = 36=> 4x + 12 = 36 => x = 6The numbers are 6, 8, 10 and 12.Sum of their squares = 62 + 82 + 102 + 122 = 36 + 64 + 100 + 144 = 344.
Number System Which choice provides the answer in the following : If 2 * 3 = 36, 5 * 4 = 400, 6 * 2 = 144, 3 * 3 = 81; then, 5 * 5 = ? 625 325 425 525 625 325 425 525 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP 625
EXAMIANS