Number System If the sum of four consecutive numbers is 370, which the following is the third lowest number among them 91 89 90 92 91 89 90 92 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the four consecutive numbers be x, (x + 1), (x + 2), (x + 3) thenx + (x + 1) + (x + 2) + (x + 3) = 370= 4x + 6 = 370∴ x = 364/4 = 91∴ third lowest number among them = x + 1= 91 + 1 = 92
Number System A bag contains four red, six black and seven green balls. Three balls are drawn randomly. What is the probability that the balls drawn contain exactly two red balls ? 45/340 58/340 39/340 51/340 45/340 58/340 39/340 51/340 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Total balls = 4 + 6 + 7 = 17∴ n(S) = 17C1 = 680Two red balls can be selected from four red balls in 4C2 = 6 ways.and the third ball can be selected from the remaining 13 balls in 13C1 = 13 ways.∴ P (E) = 13x6/680 = 39/340
Number System Which one of the following represents the sum of the first n even numbers? N(N + 1) N2+ 1 N2 N(N – 1) N(N + 1) N2+ 1 N2 N(N – 1) ANSWER EXPLANATION DOWNLOAD EXAMIANS APP N (N + 1)
Number System Find the number, when 15 is subtracted from 7 times the number, the result is 10 more than twice of the number 5 4 7.5 15 5 4 7.5 15 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the number be x.7x -15 = 2x + 10 => 5x = 25 => x = 5
Number System If a number is subtracted from its square we get 272. Find the number? 22 24 14 17 22 24 14 17 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP x2 – x = 272 => x =17
Number System Which one of the following numbers is exactly divisible by 11? 315624 245642 415624 235641 315624 245642 415624 235641 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP (4 + 5 + 2) - (1 + 6 + 3) = 1, not divisible by 11.(2 + 6 + 4) - (4 + 5 + 2) = 1, not divisible by 11.(4 + 6 + 1) - (2 + 5 + 3) = 1, not divisible by 11.(4 + 6 + 1) - (2 + 5 + 4) = 0. So, 415624 is divisible by 11.
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