Number System Thrice the square of a natural number decreased by 4 times the number is equal to 50 more than the number. The number is: 5 6 4 10 5 6 4 10 ANSWER DOWNLOAD EXAMIANS APP
Number System How many numbers between 300 and 800 can be by using digits 2, 4, 5, 6 and 0 ? 36 48 56 52 36 48 56 52 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP ∴ Reqd . numbers = 3 x 4P2 = 3 x 12 = 36
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 ? 89/190 92/190 91/190 90/190 89/190 92/190 91/190 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 On dividing number by 56, we get 29 as remainder. On dividing the same number by 8, what will be the remainder? 4 5 6 7 4 5 6 7 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let x be the number and y be the quotient. Then, x = 357 * y + 39= (17 * 21 * y) + (17 * 2) + 5= 17 * (21y + 2) + 5.Required remainder = 5.
Number System The average age of seven boys sitting in a row facing North is 26 years. If the average age of first three boys is 19 years and the average age of last three boys is 32 years, what is the age of the b 30 years 31 years 28 years 29 years 30 years 31 years 28 years 29 years ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Age of the fourth boy = (26 x 7 - 3 x 19 - 3 x 32) years = (182 - 57 - 96) years = 29 years
Number System In how many different ways can the letters of the word ANATOMY be arranged ? 2508 2510 2520 2504 2508 2510 2520 2504 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Here total letters are 7 but A comes twice.Therefore, Numbers of arrangements = 7!/2! = 2520