TAMIL NADU STATE BOARD CLASS 12 STATISTICS 2025

An additive model of time series with components, T, S, C and I is :

The first National Statistics Day was celebrated on ____________.

Vital Index measures :

Rates of Vital events are usually measured as :

In a recent survey, conducted among 2000 randomly selected graduates in a district, 367 of them are IAS aspirants. Calculate the proportion of IAS aspirants among the graduates in the district.

Define degrees of freedom.

What are the assumptions of ANOVA ?

Given that $\operatorname{cov}(x, y)=9.3$, variance of $x=10.1$, variance of $y=11.9$. Find $r$.

What are the types of regression ?

What is circular test ?

What is a time series ?

What is the formula used to compute infant mortality rate ?

The number of children born in a city during a period was 3,907 and the total population of the city in that period was 20,00,000. Find the crude birth rate of the city.

Describe Decision Table.

State the properties of $\chi^2$ distribution.

Write the model ANOVA table for one-way classification.

Write any three uses of correlation.

What is cyclical variation ?

State the characteristics of a project.

Calculate the consumer price index number for 2015 on the basis of 2000 from the following data by using the Aggregate Expenditure method. 2000 2015 Wheat 10 15 20 Rice 12 30 36 Ghee 2 160 200 Sugar 4 40 40 Price Commodity Quantity

The number of women at reproductive age in a district is 70,000. Also the number of live births and infant deaths registered in the district are respectively 10,000 and 70. Which mortality rate you will calculate ? What is its value ?

The following are the information about the number of persons who are affected by Diabetes and Lung Cancer and the number of persons died due to each cause of death during a calendar year in two different districts: Affected Died Affected Died Diabetes 20,000 325 22,000 400 Lung cancer 19,500 300 21,225 380 District A No. of persons District B No. of persons Cause of Death Find the Illness specific death rates for the two districts. Also, compare health conditions of both the districts with reference to these two causes of death.

Given the following lines of regression $4X-5Y=-33$ and $20X-9Y=107$. Find the mean values of $X$ and $Y$.

A test was conducted with 6 students before and after the training programme. Their marks were recorded and tabulated as shown below. Test whether the training was helpful in improving their scores. Before training 100 160 113 122 120 105 After training 120 155 120 128 115 100

A company producing LED bulbs finds that mean life span of the population of its bulbs is 2000 hours with a standard deviation of 150 hours. A sample of 100 bulbs randomly chosen is found to have the mean life span of 1950 hours. Test, at 5% level of significance, whether the mean life span of the bulbs is significantly different from 2000 hours.

Estimate the value of production for the year 1995 by using the method of least squares from the following data. Year 1990 1991 1992 1993 1994 Production (1000 tons) 70 72 88 90 92

A test was given to five students taken at random from XII class of three schools of a town. The individual scores are : School I 9 7 6 5 8 School II 7 4 5 4 5 School III 6 5 6 7 6 Carry out the one-way ANOVA.

Following data gives the yield of foodgrains in India for the years 1990 - 91 to 1999 - 2000. Find the trend values using 4 - year moving averages. Year 1990-91 91-92 92-93 93-94 94-95 95-96 96-97 97-98 98-99 1999-2000 Yield (kg/hectare) 626 734 535 727 652 715 756 860 909 798

Calculate the regression equation of X on Y from the data given below, $x$ 7 4 6 9 3 8 $y$ 8 5 4 8 3 6

A random sample of 5 college students is selected and their marks in Tamil and English are found to be : Tamil 85 60 73 40 90 English 93 75 65 50 80 Calculate Spearman’s rank correlation coefficient.

A normal population has mean $\mu$ (unknown) and variance 9. A sample of size 9 observations has been taken and its variance is found to be 5.4. Test the null hypothesis $H_0 : \sigma^2=9$ against $H_1 : \sigma^2>9$ at 5% level of significance.

Calculate the price indices from the following data by applying (1) Laspeyre’s method (2) Paasche’s method and (3) Fisher ideal number by taking 2010 as the base year. Prices Quantities Prices Quantities A 20 10 25 13 B 50 8 60 7 C 35 7 40 6 D 25 5 35 4 Commodity 2010 2011

The following are the information about the number of persons who are affected by Diabetes and Lung Cancer and the number of persons died due to each