Number System A number consists of 3 digit whose sum is 10. The middle digit is equal to the sum of the other two and the number will be increased by 99 if its digits are reversed. The number is: 145 253 352 370 145 253 352 370 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the middle digit be x. Then, 2x = 10 or x = 5.So, the number is either 253 or 352. Since the number increases on reversing the digits, so the hundred's digit is smaller than the unit's digit. Hence, required number = 253.
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 24 18 42 81 24 18 42 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 In a pair of fractions, fraction A is twice the fraction B and the product of two fractions is 2/25. What is the value of fraction A? 2/5 1/25 Data inadequate 1/5 2/5 1/25 Data inadequate 1/5 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP A = 2B => B = 1/2 A, so, AB = 2/25 1/2 A2 = 2/25A2 = 4/25 A = 2/5
Number System The sum of the squares of three numbers is 138, while the sum of their products taken two at a time is 131. Their sum is: 30 40 20 None of these 30 40 20 None of these ANSWER DOWNLOAD EXAMIANS APP
Number System Two numbers are in the ratio 3:5. If 9 be subtracted from each, they are in the ratio of 9:17. The first number is: 18 30 36 27 18 30 36 27 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP (3x-9):(5x-9) = 9:17 x = 12 => 3x = 36
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