*Question:* a recent study of 35 students were asked the cost...

###### Question details

A recent study of 35 students were asked the cost of their monthly internet charges. The results are shown in the following table:

Cost ($) |
Frequency (f) Number of students |

40-49 |
5 |

50-59 |
8 |

60-69 |
16 |

70-79 |
4 |

80-89 |
2 |

Calculate: (a) the mean [Answer to 2 dp]

(b) the standard deviation [Answer to 2 dp]

(c) the interquartile range [Answer to whole number]

2.For the standard normal distribution, find:

P(0<z<1.25)

3.The probability of having a baby boy is 0.5. In a family of 5 children what is the probability that all 5 will be boys? [Give answer to 4 decimal places]