Number System Which one of the following is the sum of the numbers 1, 3, 5, 7, 9…. up to nth number? N2 N(N + 1)/2 N(N + 1) N2 + 1 N2 N(N + 1)/2 N(N + 1) N2 + 1 ANSWER DOWNLOAD EXAMIANS APP
Number System A plot of 650 sq ft is available at the rate of Rs 6500 per sq ft. If 13% of the total cost of the plot is to be paid for booking the plot, what is the booking amount, (in Rs) ? Rs. 549250 Rs. 507250 Rs. 519850 Rs. 536250 Rs. 549250 Rs. 507250 Rs. 519850 Rs. 536250 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Total cost of plot= 650 x 6500 = 4225000Booking amount = 13% of (4225000) = 4225000 x 13/100 = 549250
Number System The sum of a number and its reciprocal is one-eighth of 34. What is the product of the number and its square root? 32 8 None of these 27 32 8 None of these 27 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the number be x. Then,x + 1/x = 34/8 8x2 - 34x + 8 = 0 4x2 - 17x + 4 = 0 (4x - 1)(x - 4) = 0 x = 4required number = 4 * √4 = 4 * 2 = 8.
Number System The sum of two numbers is 25 and their difference is 13. Find their product. 114 104 325 315 114 104 325 315 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the numbers be x and y. Then x + y = 25 and x - y = 13.x = 19; y = 6xy = 19 * 6 = 114
Number System A two-digit number is such that the product of the digits is 8. When 18 is added to the number, then the digits are reversed. The number is: 81 18 42 24 81 18 42 24 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the ten's and unit's digit be x and 8/x respectively. Then, (10x + 8/x) + 18 = 10 * 8/x + x 9x2 + 18x - 72 = 0 x2 + 2x - 8 = 0 (x + 4)(x - 2) = 0 x = 2 So, ten's digit = 2 and unit's digit = 4. Hence, required number = 24.
Number System If (47)² is added to the square of a number the answer thus obtained is 2290. What is the number ? 8 7 9 10 8 7 9 10 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the no. be x Therefore, x² + (47)² = 2290Therefore, x² = 2290 - 2209 = 81Therefore, x = 9
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