SOLUTION
Given the question in the image, the following are the solution steps to answer the question.
STEP 1: Write the formula for finding the average

STEP 2: Get the total reading time for the first 10 people

STEP 2: Get the total reading time for the remaining 5 people

STEP 3: Calculate the average reading time for the entire book club each day

Hence, the average reading time for the entire book club each day is 55 minutes per day