The scores X1 and X2 in papers 1 and 2 of an examination are normally distributed with means 24.3 and 31.2 respectively and standard deviations 3.5 and 3.1 respectively The final mark for each candidate is found by calculating 2X1+1.5X2. Find the probability that a random sample of 8candiates will have a mean final mark of less than 60.(adsbygoogle = window.adsbygoogle || []).push({});

what i have done so far is F~N(95.4,70.6225) and Sample mean of F, N (95.4,70.6225/8)

P(sample mean of F<60)

... then unable to do alrdy because the z-score is too large

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Sampling- linear combinations

Loading...

Similar Threads for Sampling linear combinations |
---|

A Sample Test | Component Lifetime |

I Sampling weights |

I Sampling from a multivariate Gaussian distribution |

I Standard Deviation Versus Sample Size & T-Distribution |

A Akaike information small sample AICc |

**Physics Forums | Science Articles, Homework Help, Discussion**