Number System What is the sum of 1 + 2 + 3+ ... + 27 ? 343 378 382 396 343 378 382 396 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Sum = 27 x (27 + 1)/2= 27 x 28/2= 27 x 14= 378
Number System The sum of the ages of a son and father is 65 years. After 5 years the age of father will be double of the age of son. What is the age of son ? 19 years 18 years 17 years 20 years 19 years 18 years 17 years 20 years ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the age of the son be x and the age of the father be y.Therefore, x + y = 65 ..........(i)or, 2 x (x + 5) = (y + 5)or, 2x + 10 = y + 5or, 2x - y = 5 ...................(ii)From equations (i) and (ii), x = 20, y = 45
Number System The product of two consecutive odd numbers is 6723. Find is the greater number. 80 85 77 83 80 85 77 83 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the first odd number be x.Then, the other odd number would be x + 2.∴ x(x+2) = 6723= x2 + 2x = 6723= x2 + 2x = 6723= x2 + 2x - 6723 = 0= x2 + 83 - 81 x - 6723 = 0= x(x+83) - 81 (x + 83) = 0= (x + 83) (x - 81) = 0= (x + 83) (x - 81) = 0= x - 81 = 0∴ x = 81Hence, greater number = x + 2 = 81 + 2 = 83
Number System 17580 x 1.8 - 13720 x 2.1 = ? x 2.4 1140 1160 1180 1120 1140 1160 1180 1120 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP 2.4 x ? = 31644 - 28812 = 2832∴ ? = 2832/2.4= 1180
Number System What is the missing number in this series? 8 2 14 6 11 ? 14 6 18 12 2 3 7 9 2 3 7 9 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP 9
Number System The number of prime factors of (6)10×(7)17×(55)27 91 101 61 41 91 101 61 41 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP 91