Only do number 23 i'll mark brainliest

Answer soon(fast) 15 pts-brainliest? for right answer with small explination a restaurant catered a party for 40 people. a child’s dinner (c) cost $11 and an adult’s dinner (a) cost $20. the total cost of the dinner was $728. how many children and adults were at the party? use the table to guess and check.(i couldn't get the graph onto the question)                                8 children and 32 adults9 children and 31 adults10 children and 30 adults12 children and 28 adults

When i add money am i supposed to make it like this 7+12 or 7.00+12.00 because i got 19 dollars for my answer

What is the value of x? enter your answer in the box. photo attached.