Number System The average age of seven boys sitting in a row facing North is 26 years. If the average age of first three boys is 19 years and the average age of last three boys is 32 years, what is the age of the b 30 years 31 years 29 years 28 years 30 years 31 years 29 years 28 years ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Age of the fourth boy = (26 x 7 - 3 x 19 - 3 x 32) years = (182 - 57 - 96) years = 29 years
Number System Simplify the 121 * 175 + 363 * 275 316600 363000 328100 None of these 316600 363000 328100 None of these ANSWER EXPLANATION DOWNLOAD EXAMIANS APP 121 * 175 + 363 * 275 => 121 * 175 + 121 * 3 * 275121 * 175 + 121 * 825= 121 * (175 + 825) = 121000
Number System The average of five consecutive even numbers A, B, C, D and E is 42. What is the product of B and D ? 1760 3289 2476 4589 1760 3289 2476 4589 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP A + B + C + D + E/5 = 42∴ C = 42, ∴ B = 40, ∴ D = 44∴ B x D = 40 x 44 = 1760
Number System If the three fourth of a number is subtracted from the number; the value so, obtained is 163. What is that number ? 652 689 692 678 652 689 692 678 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Number x (1 - 3/4) = 163∴ Number = 163 x 4 = 652
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 32 27 8 None of these 32 27 8 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 value of ? in the following equations ? 72/? = ?/50 60 80 100 40 60 80 100 40 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP (?)² = 72 x 50= (6 x 6 x 2) x (5 x 5 x 2)= (6 x 5 x 2)² = (60)²∴ ? = 60