Number System Which one of the following is the sum of the numbers 1, 3, 5, 7, 9…. up to nth number? N2 + 1 N2 N(N + 1) N(N + 1)/2 N2 + 1 N2 N(N + 1) N(N + 1)/2 ANSWER DOWNLOAD EXAMIANS APP
Number System The difference between 45% of a number and 18% of the same number is 145.8. What is 30% of that number ? 141 245 188 162 141 245 188 162 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the number be x.45% of x - 18% of x = 145.8∴ x/100 (45 - 18) = 145.8∴ x = 145.8 x 100/27 = 540∴ 30% of 540 = 540 x 30/100 = 162
Number System The peresent age of the father and the son are in the ratio of 8:3. After 12 years the ratio of their ages will be 2:1. What is the sum of the present age of the father and the son ? 68 years 69 years 67 years 66 years 68 years 69 years 67 years 66 years ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the present age of the father be 'x' and that of the son be 'y'. Then x/y = 8/3∴ 3x = 8y Further, x + 12/y + 12 = 2/1 ∴ x + 12 = 2y + 24 ∴ x - 2y = 12 ......(ii)From eqn (i) and (ii), x = 48, y = 18 ∴ sum = 66 yrs.
Number System 7.8 x 4.5 x 4.2/0.14 = ? 1032 1012 1087 1053 1032 1012 1087 1053 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP 7.8 x 4.5 x 4.2/0.14 = 1053
Number System What is the difference between the local value of 7 and 5 in the number 2574? 570 430 403 413 570 430 403 413 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP 500 – 70 = 430
EXAMIANS