Number System The product of two natural numbers is 17. Then, the sum of the reciprocals of their squares is: 1/289 290/289 289/290 289 1/289 290/289 289/290 289 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the numbers be a and b. Then,ab = 17, a = 1 and b = 17So, 1/a2 + 1/b2 = (a2 + b2)/a2 b2 = (12 + 172)/(1 * 17)2 = 290/289
Number System If the fraction 8/6, 7/5, 18/13, 9/5 and 7/11 are arranged in descending order of their values, which one will be the second ? 3/4 1/9 2/7 7/5 3/4 1/9 2/7 7/5 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP 8/6 = 1. 333, 7/5 = 1.4, 18/13 = 1.3849/5 = 1.8 and 7/11 = 0.636Therefore, Descending order is 9/5 > 7/5 > 18/13 > 8/6 > 7/11Therefore Second fraction is 7/5
Number System The sum of two numbers is 25 and their difference is 13. Find their product. 325 315 114 104 325 315 114 104 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 7.8% of 12.5 + 2.5% of 161 = ? 5 12 9 2 5 12 9 2 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP 7.8 x 12.5/100 + 2.5 x 161/100= 0.975 + 4.025= 5
Number System (√6 + 1)² = ? + 2√6 5 7 6 8 5 7 6 8 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP ? = (√6 + 1)² - 2√6= (√6)² + 2 x √6 + 1 + 1² - 2√6= 6 + 2√6 + 1 - 2√6 = 6 + 1 = 7
Number System If (17)3 is subtracted from the square of a number, the answer so obtained is 2143. What is the number ? 84 81 82 83 84 81 82 83 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP x² - (17*17*17) = 2143or x² = 2143 + 4913 = 7056∴ x = 84
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