Sebenta de Exercícios Resolvidos - O DGE - UBI

7.2.
RESOLUÇÕES 73
d)
⇔
S Agregada = I Agregado
2000 −
95
(0.1+r) 2 − 100
0.1+r
2 + r
⇔ r = 0.24799
=
50
(0.1 + r) 2
S Agregada = 2000− 95
(0.1+0.24799) 2 − 100
0.1+0.24799
= 412. 88
2+0.24799
I Agregada = 200 × ( 0.5 2
0.1+0.24799)
= 412. 88
C Agregado = 200×
⎛
⎝70−(
0.5
0.1+0.24799) 2 + 60+ 0.5
0.5
( 0.1+0.24799)+(1−0.1)( 0.24799+0.1) 2 ⎞
⎠
1+0.24799
1
1+ 1+0.24799
= 13174.
e) Se o rendimento cai inesperadamente a poupança diminui, o
que faz com que a recta da poupança se desloque para a esquerda,
fazendo subir a taxa de juro real e dimunir o investimento.
S Agregada = 200
( 0.5
2 + r (Y 1 − T 1 −
0.1 + r
− 200
( 1 + r
2 + r
) 2
)−
) ( Y 2 − T 2 + ( 0.5
0.1+r
⇔ S Agregada = 200 ( ) 2 0.5
2 + r (65 − ) − 200
0.1 + r
⇔ S Agregada =
⇔ S Agregada =
d)
) (
+ (1 − 0.1)
0.5
r+0.1
1 + r
) 2
)
( ) ( 1 + r 60 + ( 0.5
0.1+r
2 + r
50
13000 − − 12000 − 100 − 180 ( 0.5
(0.1+r) 2 0.1+r r+0.1
2 + r
95
1000 − − 100
(0.1+r) 2 0.1+r
.
2 + r
) 2
⇔
⇔
) (
+ (1 − 0.1)
0.5
r+0.1
1 + r
) 2
)
⇔
⇔
S Agregada = I Agregado
1000 −
95
(0.1+r) 2 − 100
0.1+r
2 + r
⇔ r = 0.4173
=
50
(0.1 + r) 2