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? Data inadequate 2/5 1/5 1/25 Data inadequate 2/5 1/5 1/25 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 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 ? 92/190 89/190 90/190 91/190 92/190 89/190 90/190 91/190 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 The difference between a two-digit number and the number obtained by interchange the two digits of the number is 27. If the sum of the two digits of the number is 13, what is their product ? 40 39 37 38 40 39 37 38 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the number be 10x + y.∴ 10x + y - (10y + x) = 27or 9x - 9y = 27∴ x - y = 3 .......(I)x + y = 13 .......(II)From eqn (I) and (II)x = 8 and y = 5.So the number = 85Therefore, product = 8 x 5 = 40
Number System 4550 ÷ 25% of ? = 130 125 130 140 135 125 130 140 135 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP 4550 ÷ ? x 25/100 = 130= 4550 ÷ ?/4 = 130= 4550 x 4/? = 130= ? x 130 = 4550 x 4= ? = 4550 x 4/130 = 140
Number System If three eighth of a number is 141. What will be the approximately value of 32.08% of this number? 160 90 60 120 160 90 60 120 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP x * 3/8 = 141 => x= 376376 * 32.08/100 = 120
Number System If the difference between a number and its three fifths is 62, what is the number ? 145 175 155 165 145 175 155 165 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the number be x.∴ x - 3x/5 = 62or x = 62 x 5/2 = 155