Number System The sum of two numbers is 165 and the difference between them is 9. What is the average of these two numbers ? 83.5 82.5 84.5 85.5 83.5 82.5 84.5 85.5 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP x + y = 165x - y = 92x = 174 ∴ x = 87 and y = 78∴ x + y/2 = 165/2 = 82.5
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 28/144 29/145 27/143 30/146 28/144 29/145 27/143 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 4550 ÷ 25% of ? = 130 140 125 135 130 140 125 135 130 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP 4550 ÷ ? x 25/100 = 130= 4550 ÷ ?/4 = 130= 4550 x 4/? = 130= ? x 130 = 4550 x 4= ? = 4550 x 4/130 = 140
Number System Find the greatest number which leaves the same remainder when it divides 25, 57 and 105. 16 8 18 12 16 8 18 12 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP 105 - 57 = 4857 - 25 = 32105 - 25 = 80The H.C.F of 32, 48 and 80 is 16.
Number System 2/11 of 3/7 of 8/13 of 12012 = ? 449 576 241 321 449 576 241 321 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP ? = 2 x 3 x 8 x 12012/11 x 7 x 13 = 576
Number System What is the sum of all the numbers between 300 and 1000 which are divisible by 179? 2527 2517 2506 2607 2527 2517 2506 2607 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP 358/179 ….. 895/179179(2 + 3 + 4 + 5) => 2506
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