Number System Which one of the following represents the sum of the first n even numbers? N(N + 1) N(N – 1) N2+ 1 N2 N(N + 1) N(N – 1) N2+ 1 N2 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP N (N + 1)
Number System If (17)3 is subtracted from the square of a number, the answer so obtained is 2143. What is the number ? 82 84 81 83 82 84 81 83 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP x² - (17*17*17) = 2143or x² = 2143 + 4913 = 7056∴ x = 84
Number System The sum of two numbers is 22. Five times one number is equal to 6 times the other. The bigger of the two numbers is: 15 16 10 12 15 16 10 12 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the numbers be x and (22 - x). Then,5x = 6(22 - x) 11x = 132 => x = 12So, the numbers are 12 and 10.
Number System If the following fractions 7/6, 6/7, 5/3, 8/13 and 6/5 are arranged in descending order, which will be the last in the series? 8/13 7/13 9/13 6/13 8/13 7/13 9/13 6/13 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP 7/6 = 1.166, 6/7 = 0.857,5/3 = 1.66,8/13 = 0.615,6/5 = 1.2Therefore, 5/3 > 6/5 > 7/6 > 6/7 > 8/13
Number System Of an amount, 20% of 25% of 30% is Rs 75. Then what is the original amount ? Rs. 5000 Rs. 2000 Rs. 3000 Rs. 4000 Rs. 5000 Rs. 2000 Rs. 3000 Rs. 4000 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the amount be x.∴ X x 20/100 x 25/100 x 30/100 = 75∴ X = 75 x 5 x 4 x 10/3 = 5000
Number System Find the least value of 3x + 4y if x2y3 = 6. 6 3 7 10 6 3 7 10 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP 10