Final answer:
To find the mean reading speed exceeded by a 5% chance for 21 second-grade students, one would use statistical methods with t-distribution or z-scores and tools like a TI-83+ or TI-84 calculator.
Step-by-step explanation:
To determine the value that a mean reading speed will exceed with a 5% chance in a random sample of 21 second-grade students, you would typically use a statistical method such as a t-test or z-score, depending on whether the population standard deviation is known or not. Since the grade level suggests an upper-level statistical concept and the keywords hint at a probability distribution scenario, this is most likely a reference to using the t-distribution table or z-table to find the critical value, which corresponds to the point in the distribution where only 5% of values are greater than it.
In a statistics class, students often use technological tools like a random number generator and statistical software, or functions on a calculator such as the TI-83+ or TI-84, to perform such calculations. These tools help with generating random samples, calculating sample means, sample standard deviations, and finding critical values related to probabilities.
Following the steps provided, you may need to calculate the sample mean and standard deviation, look up the appropriate critical value corresponding to a 5% chance in the upper tail of the distribution (since the question refers to exceeding a value), and then apply this to your sample statistics to find the specific mean reading speed threshold for your scenario.