3 people are in a room. Everyone shakes hands with everyone else once. How many handshakes happen?, What about 4 people?, 5 people?, 10 people?, Can you predict the answer for 20 without drawing them all?, One square table can seat 4 people. Two square tables are pushed together in a row. How many people can sit around them?, What about 3 tables?, 5 tables?, 10 tables?, 100 tables?, 4 football teams enter a competition. Every team plays every other team once. How many matches are played?, What about 5 teams?, 6 teams?, What if everyone plays each other twice?, Can you find a rule?, I add two consecutive numbers and get 15. What are my numbers?, Can you make 21?, Can every odd number be made this way?, Can an even number?, Which numbers are impossible to make?, A staircase has 1 block on the first step, 2 on the second and 3 on the third. How many blocks are needed altogether?, What about 4 steps?, 5 steps?, 10 steps?, 20 steps?, Can you create your own question like the others in the boxes?, What type of problem are you creating?, Do you know the answer?, Can you make it harder each time you answer?

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