36 workers can complete a piece of work in 12 days how many workers should be removed to complete the same work in 24 days please explain step by step

Out of the 180 students at a summer camp, 72 signed up for canoeing. there were 23 students who signed up for trekking, and 13 of those students also signed up for canoeing. use a two-way table to organize the information and answer the following question: approximately what percentage of students signed up for neither canoeing nor trekking? 72% 40% 54% 98%