Number System In a two-digit number, if it is known that its unit's digit exceeds its ten's digit by 2 and that the product of the given number and the sum of its digits is equal to 144, then the number is: 24 26 46 42 24 26 46 42 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the ten's digit be x. Then, unit's digit = x + 2. Number = 10x + (x + 2) = 11x + 2 Sum of digits = x + (x + 2) = 2x + 2 (11x + 2)(2x + 2) = 144 2x2 + 26x - 140 = 0 (x - 2)(11x + 35) = 0 x = 2Hence, required number = 11x + 2 = 24.
Number System The product of two natural numbers is 17. Then, the sum of the reciprocals of their squares is: 289/290 289 1/289 290/289 289/290 289 1/289 290/289 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 Of an amount, 20% of 25% of 30% is Rs 75. Then what is the original amount ? Rs. 2000 Rs. 3000 Rs. 4000 Rs. 5000 Rs. 2000 Rs. 3000 Rs. 4000 Rs. 5000 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 What is the sum of the local values of the digits 2, 3, 4, 5 in the number 2345? 2435 2105 2345 5243 2435 2105 2345 5243 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP 2000 + 300 + 40 + 5 = 2345