Number System Find the smallest number which should be multiplied with 520 to make it a perfect square. 120 30 None of these 55 120 30 None of these 55 ANSWER DOWNLOAD EXAMIANS APP
Number System The product of two successive numbers is 4556. Which of the following is the larger of the two numbers? 68 63 78 67 68 63 78 67 ANSWER DOWNLOAD EXAMIANS APP
Number System What should come in the place of ' ? ' in the following number series ? 2, 5, 9, 19, 37, ? 76 75 78 77 76 75 78 77 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP 2 x 2 + 1 = 5;5 x 2 - 1 = 99 x 2 + 1 = 19: 19 x 2 - 1 = 3737 x 2 + 1 = 75
Number System A box contains 5 red, 4 black and 4 blue balls. If 3 balls are drawn randomly from the box, what is the probability that there are exactly 2 blue balls in the three drawn balls ? 30/146 29/145 27/143 28/144 30/146 29/145 27/143 28/144 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Total balls = 5 + 4 + 4 = 13∴ n(S) = 13C3 = 2862 blue balls can be selected from 4 balls in 4C2 = 6 ways and the remaining one ball is to be selected from 9 balls in 9C1 = 9 ways ∴ n(E) = 6 x 9∴ P(E) = 6 x 9/286 = 27/143
Number System Find the least number with which 16200 should be multiplied, to make it a perfect cube. 36 360 45 48 36 360 45 48 ANSWER DOWNLOAD EXAMIANS APP
Number System In a two-digit number, if it is known that its unit's digit exceeds its ten's digit by 2 and that the product of the given number and the sum of its digits is equal to 144, then the number is: 42 24 26 46 42 24 26 46 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the ten's digit be x. Then, unit's digit = x + 2. Number = 10x + (x + 2) = 11x + 2 Sum of digits = x + (x + 2) = 2x + 2 (11x + 2)(2x + 2) = 144 2x2 + 26x - 140 = 0 (x - 2)(11x + 35) = 0 x = 2Hence, required number = 11x + 2 = 24.