if the mean is 250mg and the standard deviation is 75mg and 2% goes either right or left, what formula do i use to come out with a normal curve?
To graph a normal curve with given mean, standard deviation, and the percentage of data going in one direction (either right or left), you can follow these steps:
Step 1: Determine the z-score
A z-score measures the number of standard deviations an individual data point is from the mean. In this case, since you want to find the value that represents 2% of the data going either right or left, you need to find the z-score that corresponds to that percentage.
Use a z-score table or a statistical calculator to find the z-score associated with 2% (0.02) in the cumulative probabilities. For example, if you are looking for the z-score for the lower tail (left side) of the curve, you would look for the cumulative probability of 0.02.
Step 2: Calculate the raw score
Once you have the z-score, you can calculate the corresponding raw score (the value on the x-axis of the normal curve).
You can use the formula:
Raw score = Mean + (Z-score * Standard Deviation)
In this case, since you want the value for the lower tail of the curve, you would use the negative z-score derived in Step 1.
Step 3: Plot the normal curve
Now that you have the raw score, you can plot the normal curve. The mean is represented as the center point of the curve, and the standard deviation determines the spread of the curve.
You can use a graphing tool such as a graphing calculator or a statistical software to plot the normal curve based on the given mean, standard deviation, and the raw score obtained from Step 2.