Number System The sum of the two numbers is 12 and their product is 35. What is the sum of the reciprocals of these numbers? 1/35 7/32 12/35 35/8 1/35 7/32 12/35 35/8 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the numbers be a and b. Then,a + b = 12 and ab = 35.(a + b)/ab = 12/35= (1/b + 1/a) = 12/35Sum of reciprocals of given numbers = 12/35.
Number System If the sum and difference of two numbers are 20 and 8 respectively, then the difference of their square is: 28 160 180 12 28 160 180 12 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the numbers be x and y. Then, x + y = 20 and x - y = 8x2 - y2 = (x + y)(x - y) = 20 * 8 = 160.
Number System 1089/? = ?/1296 1278 1188 1082 1348 1278 1188 1082 1348 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP (?)² = 1089 x 1296(?)²= (11 x 11 x 9) x (12 x 12 x 9)(?)= 11 x 12 x 9= 1188
Number System When the square of a number is substracted from (68)², the answer so obtained is 2508. What is the number ? 46 45 47 44 46 45 47 44 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP (68)² - x² = 2508Therefore, x² = 4624 = 2508Therefore, x = root of 2116 = 46
Number System The sum of 8 consecutive odd numbers is 656. Also average of four consecutive even numbers is 87. What is the sum of the smallest odd number and second largest even number ? 160 167 158 163 160 167 158 163 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Average of 8 consecutive odd numbers = 656/8 = 82∴ Fourth number = 82 - 1 = 81∴ First numbers = 75Average of 4 even numbers = 87∴ Second even number = 87 - 1 = 86Second largest even number = 88∴ Required sum = 75 + 88 = 163
Number System The difference between a number and its three-fifth is 50. What is the number? None of these 125 100 75 None of these 125 100 75 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP x - 3/5 x = 50 => 2/5 x = 50x = (50 * 5)/2 = 125.