class 11

Math

Algebra

Statistics

Out of 30 observation 10 are $21 +d,10$ are $21 $ and other $10$ are $21 −d$ whose variance is $34 $ then $∣d∣$ is equal to (A) $1$ (B) $2 $ (C) $3 $ (D) $2 1 $

Similar Topics

determinants

matrices

binomial theorem

complex numbers and quadratic equations

sequences and series

To find out the concentration of $SO_{2}$ in the air (in parts per million, i.e., ppm), the data was collected for $30$ localities in a certain city and is presented below:

Concentration of $SO_{2}$ (in ppm) | Frequency |

$0.00−0.04$ | $4$ |

$0.04−0.08$ | $9$ |

$0.08−0.12$ | $9$ |

$0.12−0.16$ | $2$ |

$0.16−0.20$ | $4$ |

$0.20−0.24$ | $2$ |