Number System A two-digit number is such that the product of the digits is 8. When 18 is added to the number, then the digits are reversed. The number is: 42 18 81 24 42 18 81 24 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the ten's and unit's digit be x and 8/x respectively. Then, (10x + 8/x) + 18 = 10 * 8/x + x 9x2 + 18x - 72 = 0 x2 + 2x - 8 = 0 (x + 4)(x - 2) = 0 x = 2 So, ten's digit = 2 and unit's digit = 4. Hence, required number = 24.
Number System Of an amount, 20% of 25% of 30% is Rs 75. Then what is the original amount ? Rs. 4000 Rs. 5000 Rs. 2000 Rs. 3000 Rs. 4000 Rs. 5000 Rs. 2000 Rs. 3000 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 3√103820 x 3√274620 = ? 3065 3035 3055 3045 3065 3035 3055 3045 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP 3√103820 = 47 and 3√274620 = 65 ∴ ? = 47 x 65 = 3055
Number System The sum and the product of two numbers are 25 and 144 respectively, the difference of the number is? 3 7 5 11 3 7 5 11 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP x + y = 25xy = 144(x- y)2 = (x + y)2 – 4xy(x- y)2 = 625 – 576 => (x – y) = 7
Number System If the difference between a number and its 2/5 is 240, find the number. 400 480 360 440 400 480 360 440 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 In how many different ways can the letters of the word ANATOMY be arranged ? 2504 2520 2508 2510 2504 2520 2508 2510 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Here total letters are 7 but A comes twice.Therefore, Numbers of arrangements = 7!/2! = 2520
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