The rules which tell which calculations are done before others in an expression

Student price tickets to a movie are $1 and non student tickets are $2 . 350 tickets are sold and the total amount made is $450. there were 250 student tickets sold . true or false .

You give a $4 tip for a meal that cost $22. approximately what percent of the bill was your tip?

In trapezoid abcd, ac is a diagonal and ∠abc≅∠acd. find ac if the lengths of the bases bc and ad are 12m and 27m respectively.