Number System What is the sum of all even numbers from 1 to 701? 122500 123850 122550 122850 122500 123850 122550 122850 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP 700/2 = 350350 * 351 = 122850
Number System In a five-litre mixture of milk and water the portion of water is 30%. How much milk should be added to the mixture so that the portion of water reduces to 5% ? 21 litre 25 litre 29 litre 17 litre 21 litre 25 litre 29 litre 17 litre ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Original mixture = 5 litre; Milk = 3.5 litre;Water = 1.5 litre Let x litre of milk be added so thatthe mixture becomes (x + 5) litres and the percentage of water becomes 5%So, 1.5 = (x + 5) x 5/10030 = x + 5∴ x = 25 litre
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 92/190 89/190 91/190 90/190 92/190 89/190 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 Three seventh of a number is 12 more than 40% of that number. What will be the 60% of that number? 148 126 248 210 148 126 248 210 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP 3/7 x – 40/100 x = 12x = 35 * 1235 * 12 * 60/100 = 252/2 = 126
Number System The sum of three consecutive multiples of 3 is 72. What is the largest number? 36 24 27 21 36 24 27 21 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the numbers be 3x, 3x + 3 and 3x + 6.Then,3x + (3x + 3) + (3x + 6) = 729x = 63x = 7Largest number = 3x + 6 = 27.
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