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 90/190 89/190 92/190 91/190 90/190 89/190 92/190 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 Of an amount, 20% of 25% of 30% is Rs 75. Then what is the original amount ? Rs. 4000 Rs. 3000 Rs. 5000 Rs. 2000 Rs. 4000 Rs. 3000 Rs. 5000 Rs. 2000 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 If the difference between a number and its 2/5 is 240, find the number. 400 480 440 360 400 480 440 360 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the no. be x Therefore x - 2x/5 = 240, Therefore, 3x/5 = 240Therefore, x = 240x5/3 = 400
Number System On dividing a number by 68, we get 269 as quotient and 0 as remainder. On dividing the same number by 67, what will be the remainder? 3 2 0 1 3 2 0 1 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Number = 269 * 68 + 0 = 1829267) 18292 (273 18291 -------- 1Required number = 1.
Number System The square root of 0.0081 is: 0.91 0.9 0.009 0.09 0.91 0.9 0.009 0.09 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP 0.09
Number System Three times the first of three consecutive odd integers is 3 more than twice the third. The third integer is: 11 15 9 13 11 15 9 13 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the three integers be x, x + 2 and x+ 4.Then,3x = 2(x + 4) + 3x = 11Third integer = x + 4 = 15.
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