13656
This solution details the calculation for a summation expression, using the provided mean of observations.
We are given 20 observations (\(x_1, \dots, x_{20}\)) with a mean \(\bar{x}=1.414\). The mean formula is \( \bar{x} = \frac{\sum_{i=1}^{n} x_i}{n} \).
Using the given values (\(n=20\)):
\( \sum_{i=1}^{20} x_i = n \times \bar{x} = 20 \times 1.414 = 28.28 \)We need to find the value of \(\sum_{i=1}^{20} 100(2x_i + 4)\). We apply summation properties:
1. Factor out the constant 100:
\( 100 \sum_{i=1}^{20} (2x_i + 4) \)2. Split the summation and simplify:
\( 100 \left( \sum_{i=1}^{20} 2x_i + \sum_{i=1}^{20} 4 \right) \)3. Use the sum of \(x_i\) and the sum of a constant (\( \sum_{i=1}^{n} c = n \times c \)):
\( 100 \left( 2 \sum_{i=1}^{20} x_i + (20 \times 4) \right) \)4. Substitute the calculated sum \(\sum_{i=1}^{20} x_i = 28.28\) and calculate:
\( 100 \left( 2 \times 28.28 + 80 \right) \) \( = 100 \left( 56.56 + 80 \right) \) = 100 (136.56) = 13656The calculated value of the summation is 13656.
What is the total number of students whose height is less than or equal to 165 cm?
What is the median height of the class?
The height which occurs most frequently in the class is
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| (b) Multiplier-Accelerator model | (ii) J. R. Hicks |
| (c) IS-LM curves | (iii) Jevous |
| (d) Real Business Cycle | (iv) Robert J. Borro |
Choose the correct option from those given below:
As per the SRS Bulletin of September 2017, the estimated death rate for Kerala is 7.6, while for Bihar it is 6. From these data which is the correct inference to draw?
Arrange the following States in descending order according to Maternal Mortality Ratio (MMR) as per the Special Bulletin of SRS, May, 2018:
(i) Assam
(ii) Bihar
(iii) Madhya Pradesh
(iv) Uttar Pradesh
Choose the correct answer from the code given below :
Which of the following statements is true for the Indian economy according to the World Bank figures for 2017?
Harrod's Growth model is given as under:
\(\begin{array}{ll} \mathrm{S}_{\mathrm{t}}=\alpha \mathrm{Y}_{\mathrm{t}} & 0<\alpha<1 \\ \mathrm{I}_{\mathrm{t}}=\beta\left[\mathrm{Y}_{\mathrm{t}}-\mathrm{Y}_{\mathrm{t}-1}\right] & \beta>0 \\ \mathrm{~S}_{\mathrm{t}}=\mathrm{I}_{\mathrm{t}} & \end{array}\)
where S t = Savings, Y t = Income, l t = Investment, t = time
In this model for economic growth, the condition for economic growth is