Number System If the sum of five consecutive even numbers A, B, C, D and E is 130, what is the product of A and E ? 780 660 720 840 780 660 720 840 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the consecutive even numbers be A = 2x, B = 2x + 2, C = 2x + 4, D = 2x + 6 and E = 2x + 8= A + B + C + D + E = 130= 10x + 20 = 130∴ x = 130 - 20/10 = 11Therefore, product of A and E= 22 x 30 = 660
Number System The sum of two numbers is 25 and their difference is 13. Find their product. 315 114 325 104 315 114 325 104 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 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 ? 92/190 90/190 89/190 91/190 92/190 90/190 89/190 91/190 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 A number consists of two digits. If 3/5 of 1/5 of the number is 9. Find the sum of its two digits? 60 8 7 12 60 8 7 12 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP x * 3/5 * 1/5 = 9x = 75 => 7 + 5 = 12
Number System The difference between the two digit number and the number obtained by interchanging its digits is 54. The difference between the digits is? Nothing can be said. 4 6 1 Nothing can be said. 4 6 1 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP (10x + y) – (10y + x) = 54x – y = 6
Number System If the difference between a number and its 2/5 is 240, find the number. 480 400 440 360 480 400 440 360 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the no. be x Therefore x - 2x/5 = 240, Therefore, 3x/5 = 240Therefore, x = 240x5/3 = 400
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