Standard Deviation of doctors' ages is figured.

The following data show the age distribution of the top 14 doctors in the emergency faculty of a local hospital. Age Frequency 35-39 2 40-44 2 45-49 1 50-54 3 55-59 4 60-64 2 Using the computational formula, calculate the Standard Deviation of doctors' ages

This job constructs a more than" and "less than" cumulative frequency polygon

The following data show the age distribution of the top 14 doctors in the emergency faculty of a local hospital. Age Frequency 35-39 2 40-44 2 45-49 1 50-54 3 55-59 4 60-64 2 Construct a "more than" and "less than" cumulative frequency polygon

Calculate the mean rent in thousands of dollars

A study on rental housing provided the following data on income and rent as a percentage of income for a sample of 5 rental units. Income ($000): 25, 35, 45, 75, 125 Rent (% income): 5, 10, 20, 30, 35 Calculate the mean rent in thousands of dollars.

Spelling error probablility is checked.

This scenario is emphasized: Our psychology department received a new statistics text for review. Prof. Smart in his review provided an interesting table of corrections. TYPE: Alterations-20%, Spelling-50%, Spelling and alterations-10% Assuming that spelling and alterations are the only possible types of corrections, calculate. The probablility of spotting a correction due to an alteration error or a spelling error. AND the probability of detecting no correction.

Probability is explained.

Two events, A and B are equally likely. The chance that either A or B happens on a given trial of an experiment is 0.70, while the chance that they both happen on a given trial is only 0.40. What is the probability that event A happens?