Răspuns :
Notam suma initiala = x
x + 30% x = 195000
x + 30/100 * x = 195000
x + 3/10 * x = 195000
x(1 + 3/10) = 195000
x(10/10 + 3/10) = 195000
x * 13/10 = 195000
x = 195000 : 13/10 = 195000 x 10/13
x = 150000, deci suma initiala a fost de 150000 lei
Sau:
195000..........130%
x......................100%
x = 195000 *100/130 = 150000 lei
x + 30% x = 195000
x + 30/100 * x = 195000
x + 3/10 * x = 195000
x(1 + 3/10) = 195000
x(10/10 + 3/10) = 195000
x * 13/10 = 195000
x = 195000 : 13/10 = 195000 x 10/13
x = 150000, deci suma initiala a fost de 150000 lei
Sau:
195000..........130%
x......................100%
x = 195000 *100/130 = 150000 lei
x + 30%x = 195000
x + 0.3x = 195000
1.3x = 195000
x = 195000/1.3
x = 150000 lei
x + 0.3x = 195000
1.3x = 195000
x = 195000/1.3
x = 150000 lei