100 ÷ half of 20 = What is the answer and steps Half of 20 means 10 but in BODMAS rule of means multiplication So please tell steps also

Oscar and julie ashton are celebrating their 15th anniversary by having a reception hall. they have budgeted $4,500 for their reception. if the reception hall charges a $90 cleanup fee plus & 36 per person, find the greatest number of people that they may invite and still stay within their budget.