## Kerala Plus One Maths Chapter Wise Previous Questions and Answers Chapter 15 Statistics

Question 1.

Consider the following data:

Class | 10-20 | 20-30 | 30-40 | 40-50 | 50-60 |

Frequency | 6 | 15 | 13 | 7 | 9 |

a. Consider the mean of the distribution

b. Find the standard deviation of the distribution.

c. Find the coefficient of variation of the distribution. [March-2018]

Answer:

Class | f_{1} | x_{1} | f_{1}x_{1}_{ } | x^{2}_{1} | f_{1}x^{2}_{1} |

10-20 | 6 | 15 | 90 | 225 | 1350 |

20-30 | 15 | 25 | 375 | 625 | 9375 |

30-40 | 13 | 35 | 455 | 1225 | 15925 |

40-50 | 7 | 45 | 315 | 2025 | 14175 |

50 -60 | 9 | 55 | 495 | 3025 | 27225 |

50 | 1730 | 68050 |

Question 2.

a. Find the variance for the observations 2, 4, 6, 8 and 10.

b. Consider the frequency distribution

x | 5 | 10 | 15 | 20 | 25 |

f | 7 | 4 | 6 | 3 | 5 |

i. Find the mean

ii. Find the mean deviation about the mean. [March-2017]

Answer:

Question 3.

a. Suppose the mean of a certain number of observations is 50 and the sum of ail the observations is 450. Write down the number of observations.

b. Find the mean deviation about mean for the following data: [March – 2016]

Answer:

Question 4.

a. If is the mean and σ is the standard deviation of a distribution, then the coefficient of variation is ………………

b. Find the standard deviation for the following data:

Answer:

Question 5.

Consider the frequency distribution:

a. Find the mean.

b. Calculate the variance and the standard deviation. [March-2014]

Answer:

Question 6.

Consider the following frequency distribution:

a. Find the mean.

b. Calculate the variance and standard deviation. [March-2013]

Answer:

Question 7.

Consider the following data:

i.Mean

ii. Variance

iii. Standard Deviation [February – 2013]

Answer:

Question 8.

Consider the following distribution:

a. Calculate the mean of the distribution.

b. Calculate the standard deviation of the distribution. [March-2012]

Answer: