Find out the principles by which the numbers are depicted in the tables (shown in the figures below) and insert the missing number into the first table, and remove the extra number from the second table.
A teacher filled the squares of a chequered table with
Eight schoolchildren solved
If each problem is solved by
Is it possible to arrange natural numbers from 1 to
A cinema contains 7 rows each with 10 seats. A group of 50 children went to see the morning screening of a film, and returned for the evening screening. Prove that there will be two children who sat in the same row for both the morning and the evening screening.
A
Some whole numbers are placed into a
Is it possible to place the numbers
If a class of 30 children is seated in the auditorium of a cinema there will always be at least one row containing no fewer than two classmates. If we do the same with a class of 26 children then at least three rows will be empty. How many rows are there in the cinema?
Is it possible to fill an