There is a tournament at the pool, First, $$13$$ children signed up and then another $$19$$ children signed up, Six teams with an equal number of members each are needed for the tournament, At least how many more children need to sign up so that,the six teams can be formed . (2017 Math Kangaroo Problem, Level 3-4, Question \#13) 
Overseas Competition->Knowledge Point->Word Problem Modules->Unitary Method Problems->Unitary Method with One Variable
The total number of children is $$13+19=32$$, To form six teams with the same number of children in each team, we divide $$32$$ by $$6$$, $$32\div6=5$$$$\rm R$$$$2$$, The remaining $$2$$ children will need $$4$$ more children to form the sixth team. 