Number System A basket contains 5 blue, 4 green and 3 red ball. If three balls are picked at random, what is the probability that at least one is red ? 32/51 31/58 37/52 34/55 32/51 31/58 37/52 34/55 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Probability of having no red ball is9C3 / 12C3 = 21/55Probability of having at least one red ball is 1 - 21/55 = 34/55
Number System If a number is multiplied by. three-fourth of itself, the value thus obtained is 10800. What is that number ? 260 60 120 180 260 60 120 180 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the number be x.∴ x x 3x/4 = 10800= x² = 10800 x 4/3 = 14400∴ x = √14400 = 120
Number System 148 x 3.75 x 4 = 111 x ? 20 17 19 24 20 17 19 24 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP ? = 148 x 3.75 x 4/111 = 20
Number System The difference between 78% of a number and 59% of the same number is 323. What is 62% of that number ? Rs. 945 Rs. 1054 Rs. 986 Rs. 926 Rs. 945 Rs. 1054 Rs. 986 Rs. 926 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the number be x.78% of x - 59% of x = 323= 78x - 59x/100 = 323= 19x/100 = 323∴ x = 323 x 100/19 = 1700= 62% of 1700 = 1700 x 62/100 = 1054
Number System 17580 x 1.8 - 13720 x 2.1 = ? x 2.4 1140 1160 1120 1180 1140 1160 1120 1180 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP 2.4 x ? = 31644 - 28812 = 2832∴ ? = 2832/2.4= 1180
Number System The sum of the numbers is 264. If the first number be twice the second and third number be one-third of the first, then the second number is: 84 48 54 72 84 48 54 72 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the second number be x. Then, first number = 2x and third number = 2x/3.2x + x + 2x/3 = 26411x/3 = 264x = 72
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