Number System If the difference between the squares of two consecutive numbers is 47, what is the smaller number ? 23 26 25 24 23 26 25 24 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the numbers be (x + 1) and x.Therefore, (x + 1)² - x² = 47x² + 2x + 1 - x² = 472x + 1 = 47Therefore, x = 46/2 = 23
Number System What will be the next number in the following number series ? 162 191 177 182 162 191 177 182 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP 1² + 1, 3² + 3, 5² + 5, 7² + 7
Number System If one-third of one fourth of a number is 15, then three-tenth of that number is: 35 54 25 45 35 54 25 45 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the number be x. Then,1/3 of 1/4 of x = 15x = 15 * 12 = 180So, required number = (3/10 * 180) = 54.
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 ? 27/143 30/146 28/144 29/145 27/143 30/146 28/144 29/145 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 If the difference between a number and its three fifths is 62, what is the number ? 165 175 145 155 165 175 145 155 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the number be x.∴ x - 3x/5 = 62or x = 62 x 5/2 = 155
Number System 9 3/4 + 7 2/17 - 9 1/15 = ? 9 817/1020 7 719/1020 7 817/1020 9 719/1020 9 817/1020 7 719/1020 7 817/1020 9 719/1020 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Given sum = 9 + 3/4 + 7 + 2/17 - (9 + 1/15)= (9 + 7 - 9) + (3/4 + 2/17 - 1/15)= 7 + (765 + 120 - 68)/1020 = 7 817/1020