Number System Which one of the following represents the sum of the first n even numbers? N(N + 1) N2 N(N – 1) N2+ 1 N(N + 1) N2 N(N – 1) N2+ 1 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP N (N + 1)
Number System Which one of the following numbers is exactly divisible by 11? 245642 235641 415624 315624 245642 235641 415624 315624 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.
Number System Three numbers are in ratio of 3: 4 :5. If the sum of first & third numbers is more than second number by 52, which will be largest number? 23 34 65 78 23 34 65 78 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP 65
Number System A number exceeds by 25 from its 3/8 part. Then the number is? 39 40 32 35 39 40 32 35 ANSWER DOWNLOAD EXAMIANS APP
Number System The average of 7 numbers is 15, that of the first three is 6 and that of the last three is 23. What is the fourth number? 15 18 7 13 15 18 7 13 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP 4th No. = (Total of 7 Nos) - (Total of first three + total of last 3) = (15 x 7) - (6 x 3 + 23 x 3) = 105 - (18 + 69) =105 - 87 = 18
Number System The difference between a two-digit number and the number obtained by interchanging its two digits is 45. The sum of the digit of the number is 9. What is the product of the two digits of the number? 14 15 12 13 14 15 12 13 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the number be 10x + y.Therefore, x + y = 9 ..................(i)10x + y - (10y + x) = 4510x + y - 10y - x = 45Therefore, x - y = 5 ..................(ii)From (i) and (ii), x = 7, y = 2Number = 72Therefore, = x x y = 7 x 2 = 14
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