There are 40 tables in a library, with 30% of them seating 4 people. The tables remaining only seat 22 people. How many seats are there in the library?
30% of 40 can be calculated as 40×0.3=12. So 12 tables seat 4 people, which gives 12×4=48 seats. There are a remaining 22 seats, so do 48+22=70 seats in total
