Number System If 5/7 of a number is 145, what is 180% of that number ? 345.4 365.4 355.4 375.4 345.4 365.4 355.4 375.4 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the number be x.∴ x x 5/7 = 145∴ x = 145 x 7/5 = 203Now, 203 x 180/100 = 365.4
Number System If x + y = 61 and xy = 888, What is the value of x²+ y² ? 1975 1965 1945 1955 1975 1965 1945 1955 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 The sum of three consecutive numbers is 87. The greatest among these three number is: 30 29 26 28 30 29 26 28 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the numbers be x, x + 1 and x + 2 Then,x + (x + 1) + (x + 2) = 873x = 84x = 28Greatest number, (x + 2) = 30.
Number System The simplest form of 1.5 : 2.5 is : 3 : 5 17 : 19 5 : 7 13 : 11 3 : 5 17 : 19 5 : 7 13 : 11 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP 3 : 5
Number System The sum of a number and its reciprocal is one-eighth of 34. What is the product of the number and its square root? None of these 27 8 32 None of these 27 8 32 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the number be x. Then,x + 1/x = 34/8 8x2 - 34x + 8 = 0 4x2 - 17x + 4 = 0 (4x - 1)(x - 4) = 0 x = 4required number = 4 * √4 = 4 * 2 = 8.
Number System What is the sum of all the composite numbers up to 20? 130 128 132 131 130 128 132 131 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP 4 + 6 + 8 + 9 + 10 + 12 + 14 + 15 + 16 + 18 = 132