A man has 2 times as many mangoes as his neighbour. Together they have 12 mangoes. How many mangoes does the neighbour have?

ok, lets say the neighbor has x mangoes. this means that
the man has twice that or 2x. so together means:

x + 2x =
12                            combine like terms

3x =
12                                  divide both sides by
3

x = 4

since the neighbor had
x mangoes, then this means the neighbor had 4 mangoes.