Let the number of mangoes the man has be M. As he has twice the number that his neighbor has, the number of mangoes with his neighbor is M/2
Together they have 12 mangoes. This gives M + M/2 = 12
=> (3/2)*M = 12
=> M = (2/3)*12
=> M = 8
The neighbor of mangoes with the neighbor is 8/2 = 4.
The neighbor has 4 mangoes.
If they have 12 total, your starting equation should be:
3a=12 (consolidating the equation)
Narrowing down to the variable by dividing by 3 on each side):
The neighbor has 4 and he has 8.
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.