InterviewSolution
| 1. |
The average of 7 numbers is 21. The average of first and sixth numbers is 19 and that of the third, fifth and seventh numbers is \(24\frac{1}{3}\). If the second number is less than the fourth number by 8, then the fourth number is1). 142). 223). 254). 27 |
|
Answer» We know that, Average = Sum of all observations/NUMBER of observations According to the given information, Average of 7 numbers is 21 ? The average of first and sixth numbers is 19 first number + sixth number = 19 × 2 = 38 And, SINCE Average of the third, fifth and seventh numbers is $(24\frac{1}{3})$ ∴ third number + fifth number + seventh number $(= \;24\frac{1}{3}\; \times 3\; = \;73)$ Now, since the second number is less than the FOURTH number by 8, let the second number be X thus, fourth number would be x + 8. Thus, 21 = (sum of all seven numbers)/7 $(\Rightarrow \frac{{x\; + \;x\; + \;8\; + \;73\; + \;38\;}}{7} = 21)$ ⇒ 2x + 119 = 147 ⇒ 2x = 28 ⇒ x = 14 Hence the fourth number = 14 + 8 = 22 |
|