Question

75℅. De _____=R$1800

Answer 1

X= (porcentagem)×(Capital)
X= P×C

"75% = 75÷100 = 0,75"

X= 0,75×1800
X = 1350

Answer 2

75 % ------1800
100%-----1800 +x

(1800 + x ) . 75 = 1800 .100
aplica a distributiva
1800 .75 + x .75 =180000
75 x= 45000
x =600        então 1800 +x =  1800 + 600 =2400