Number System An urn contains 9 blue, 7 white and 4 black balls. If 2 balls are drawn at random, then what is the probability that only one ball is white ? 90/190 91/190 89/190 92/190 90/190 91/190 89/190 92/190 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Total possible outcomes = 20C2 = 20 x 19/1 x 2 = 190Total favourable outcomes = 7C1 x 13C1 = 7 x 13 = 91∴ Required probability = 91/190
Number System √343 = ? 21 19 18 20 21 19 18 20 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP ? = √343 = 18
Number System {(742)² ÷ 36} ÷ 2 = ? 421.5 423.5 422.5 420.5 421.5 423.5 422.5 420.5 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP ? = (174 x 174/36) ÷ 2 = 841/2 = 420.5
Number System 84 * 29 + 365 = ? 2436 - 2071 2801 - 2801 2436 - 2071 2801 - 2801 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP - 84 * (30 - 1) + 365= - (84 * 30) + 84 + 365= - 2520 + 449 = - 2071
Number System The sum of two numbers is 25 and their difference is 13. Find their product. 315 104 114 325 315 104 114 325 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the numbers be x and y. Then x + y = 25 and x - y = 13.x = 19; y = 6xy = 19 * 6 = 114
Number System What should come in place of the question mark (?) in the following number series ? 888 888 444 148 ? 7.4 29 33 35 37 29 33 35 37 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP 888 ÷ 1 = 888888 ÷ 2 = 444444 ÷ 3 = 148148 ÷ 4 = 3737 ÷ 5 = 7.4
EXAMIANS