Question

pedro gastou tres quartos do q possuia e mais 80,00 ficou com 3/20 da quantia primitiva quanto possuia

Answer 1

$\frac{3}{4}x+80+ \frac{3}{20}x=x\\\\15x+1600+3x=20x\\\\18x+1600=20x\\20x-18x=1600\\2x=1600\\x= \frac{1600}{2}\\\\x=800\\Pedro\ tinha\ 800,00.$