Answer:76.9 pounds
Step-by-step explanation: you subtract 5.5 pounds from the 82.4 pounds to get your answer
Since each table had 7 women and 3 men at each table, that would mean each table has 10 people. Since there are 9 tables he was waiting on, and 10 people at each table, multiply 9 x 10, and you will find that he served 90 people in total.
The detailed explanation of the question is provided in the attached image.
Hope this helps :)