Number System The sum of three consecutive even numbers is 252. What is the sum of the smallest and the largest numbers? 170 171 168 169 170 171 168 169 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP 168
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: 253 145 370 352 253 145 370 352 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 If a + b = 16 and ab = 68, what is the value of a² + b² ? 124 116 112 120 124 116 112 120 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP a + b = 16 Therefore, (a+b)² = (16)² = 256 a² + b² + 2ab = 256Therefore, a² + b² = 256 - 2 x 68Therefore, a² + b² = 256 - 136 = 120
Number System An urn contains 9 blue, 7 white and 4 black balls. If 2 balls are drawn at random, then what is the probability that only one ball is white ? 91/190 89/190 92/190 90/190 91/190 89/190 92/190 90/190 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Total possible outcomes = 20C2 = 20 x 19/1 x 2 = 190Total favourable outcomes = 7C1 x 13C1 = 7 x 13 = 91∴ Required probability = 91/190
Number System A gardener wants to plant trees in his garden in such a way that the number of trees in each row should be the same. If there are 4 rows or 5 rows or 6 rows, then no tree will be left. Find the least 30 240 60 120 30 240 60 120 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP The least number of trees that are required = LCM(4, 5, 6) = 60.
Number System If the sum of the two numbers is 22 and the sum of their squares is 404, then the product of the numbers is: 40 80 88 44 40 80 88 44 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the numbers be x and y. Then, (x + y) = 22 and x2 + y2 = 404 Now, 2xy = (x + y)2 - (x2 + y2) 2xy= 222 - 404 = 484 - 404 = 80xy = 40
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