Number System What should come in the place of ' ? ' in the following number series ? 2, 5, 9, 19, 37, ? 76 77 78 75 76 77 78 75 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP 2 x 2 + 1 = 5;5 x 2 - 1 = 99 x 2 + 1 = 19: 19 x 2 - 1 = 3737 x 2 + 1 = 75
Number System If a + b = 16 and ab = 68, what is the value of a² + b² ? 120 112 124 116 120 112 124 116 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP a + b = 16 Therefore, (a+b)² = (16)² = 256 a² + b² + 2ab = 256Therefore, a² + b² = 256 - 2 x 68Therefore, a² + b² = 256 - 136 = 120
Number System In how many different ways can the letters of the word 'FRUGAL'be arranged ? 556 515 660 720 556 515 660 720 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP In FRUGAL there ae six difference letters Therefore, 6 ! = 6 x 5 x 4 x 3 x 2 x 1 = 720
Number System The difference between a two-digit number and the number obtained after interchanging its two digits is 36. The sum of the two digits of the number is 12. Find the lowest such possible number. 49 48 47 50 49 48 47 50 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the digits be x and yTherefore, x + y = 12 .............(1)(10y + x) - (10x + y) Therefore, y - x = 4............. (2)Solving (1) and (2), y = 8 Therefore, x = 4There are two possible numbers 48 and 84. So the lowest no. is 48.
Number System The difference between 72% of a number and 49% of the same number is 575. What is 9% of that number ? 295 275 245 225 295 275 245 225 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the no. be x.Therefore, 72% of x - 49% of x = 575Therefore, (72 - 49)% of x = 575Therefore, 9% of x = 575/23 x 9 = 225
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