Number System Find the least number with which 16200 should be multiplied, to make it a perfect cube. 48 45 36 360 48 45 36 360 ANSWER DOWNLOAD EXAMIANS APP
Number System The product of two natural numbers is 17. Then, the sum of the reciprocals of their squares is: 289 289/290 1/289 290/289 289 289/290 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 In how many different ways can the letters of the word 'LEASE' be arranged ? 40 80 60 None of these 40 80 60 None of these ANSWER EXPLANATION DOWNLOAD EXAMIANS APP The world LEASE consists of 5 letters in which E comes twice ∴ 51/21 = 5x4x3x2x1/2x1 = 60
Number System The difference between 35% of a number and 18% of the same number is 93.5 then what is the 40% of that number ? 225 245 220 232 225 245 220 232 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Diff = (35 - 18)% of x = 93.517x/100 = 93.5Therefore, x = 550Therefore, 40% of 550 = 220
Number System A bag contains four red, six black and seven green balls. Three balls are drawn randomly. What is the probability that the balls drawn contain exactly two red balls ? 58/340 51/340 39/340 45/340 58/340 51/340 39/340 45/340 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Total balls = 4 + 6 + 7 = 17∴ n(S) = 17C1 = 680Two red balls can be selected from four red balls in 4C2 = 6 ways.and the third ball can be selected from the remaining 13 balls in 13C1 = 13 ways.∴ P (E) = 13x6/680 = 39/340
Number System The digit in unit's place of a three digit number is thrice the digit in ten's place & the digit in hundred's place is two-third of the digit in ten's place. If the sum of three digits of number is 14 221 211 215 239 221 211 215 239 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the ten's digit be x.∴ Unit's digit = 3xHundered's digit = 2x/3∴ x + 3x + 2x/3 = 14= 3x + 9x + 2x = 14 x 3= 14x = 14 x 3= x = 3∴ Number = 239