To calculate the mean of grouped data, you need to: For Teacher Use Only QR.SP 5.D0K2.439120.M3L.3Q12 Add all the class limits and divide by the number of classes Find the sum of the midpoints multiplied by their frequencies and divide by the total number of observations Determine the highest and lowest frequencies and subtract Average the frequencies of each class

## Step 1<br />The mean of grouped data is calculated using the formula:<br />### \[ Mean = \frac{\sum (midpoint \times frequency)}{total \, number \, of \, observations} \]<br />Where:<br />- \( midpoint \) is the average of the lower and upper limits of each class.<br />- \( frequency \) is the number of observations in each class.<br />- \( total \, number \, of \, observations \) is the sum of all frequencies.<br /><br />## Step 2<br />Option A suggests adding all class limits and dividing by the number of classes. This is not the correct method for calculating the mean of grouped data.<br /><br />## Step 3<br />Option B suggests finding the sum of the midpoints multiplied by their frequencies and dividing by the total number of observations. This is the correct method for calculating the mean of grouped data.<br /><br />## Step 4<br />Option C suggests determining the highest and lowest frequencies and subtracting. This is not the correct method for calculating the mean of grouped data.<br /><br />## Step 5<br />Option D suggests averaging the frequencies of each class. This is not the correct method for calculating the mean of grouped data.