Number System The product of two natural numbers is 17. Then, the sum of the reciprocals of their squares is: 1/289 289/290 290/289 289 1/289 289/290 290/289 289 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the numbers be a and b. Then,ab = 17, a = 1 and b = 17So, 1/a2 + 1/b2 = (a2 + b2)/a2 b2 = (12 + 172)/(1 * 17)2 = 290/289
Number System If x + y = 61 and xy = 888, What is the value of x²+ y² ? 1965 1955 1975 1945 1965 1955 1975 1945 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 Difference between two numbers is 5, six times of the smaller lacks by 6 from the four times of the greater. Find the numbers? 12, 7 12, 9 10, 5 11, 6 12, 7 12, 9 10, 5 11, 6 ANSWER DOWNLOAD EXAMIANS APP
Number System 6.4 x 8.5 x 25/3.2 x 12.5 = ? 4.5 3.4 2.3 5.6 4.5 3.4 2.3 5.6 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP ? = 6.4 x 8.5 x 2.5/3.2 x 12.5 = 3.4
Number System (12.04 x 7.5 + 0.8 x 45) ÷ 3 = ? 42.6 45 54.7 42.1 42.6 45 54.7 42.1 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP (90.3 + 36) ÷ 3 = 126.3/3 = 42.1
Number System The sum of the two digits of a two-digit number is 15 and the difference between the two digits of the two digit number is 3. What is the product of the two digits of the two digit number ? 36 54 14 None of these 36 54 14 None of these ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the number be 10 x + yWhere x > yAccording to the question,x + y = 15 and x - y = 3Solving both the equations,x = 9, y = 6∴ x x y = 9 x 6 = 54