Respuesta :

Banabanana
20% = 20/100 = 0.2

x + 0.2x = 1980
1.2x = 1980
x = 1980/1.2
x = 1650  ← unknown number 
konrad509
[tex]20\%=0.2\\\\ x+0.2x=1980\\ 1.2x=1980\\ x=1650[/tex]