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 Twenty times a positive integer is less than its square by 96. What is the integer? 24 20 Cannot be determined 30 24 20 Cannot be determined 30 ANSWER DOWNLOAD EXAMIANS APP
Number System What should come in place of the question mark (?) in the given number series ? 888, 888, 444, 148, ?, 7.4 38 36 39 37 38 36 39 37 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let x be the missing number.Then888/888 = 1,888/444 = 2,444/148 = 3,148/x = 4= x = 148/4 = 37 and 37/7.4 = 5
Number System 9 3/4 + 7 2/17 - 9 1/15 = ? 9 817/1020 7 817/1020 7 719/1020 9 719/1020 9 817/1020 7 817/1020 7 719/1020 9 719/1020 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Given sum = 9 + 3/4 + 7 + 2/17 - (9 + 1/15)= (9 + 7 - 9) + (3/4 + 2/17 - 1/15)= 7 + (765 + 120 - 68)/1020 = 7 817/1020
Number System If A + B = 30 and AB = 94, What is the value of A² + B² ? 824 920 712 625 824 920 712 625 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP (A + B)² = (30)² = 900A² + B² + 2AB = 900Therefore, A² + B² = 900 - 2 x 94 = 900 - 188 = 712
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. 6 4 1 Nothing can be said. 6 4 1 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP (10x + y) – (10y + x) = 54x – y = 6