Answer
Private saving is 2500
Public saving is -200
National saving is 2300
Investment is 2300
Equilibrium interest rate is 10%
Work Step by Step
$ Y = C + I + G + NX$
$T = 1500$
Closed economies have no exports
$ Y = C + I + G + NX$
$ Y = C + I + G $
$ 10000 = 6000 + 3300 - 100*r + 1700$
$10000 = 9300 -100r +1700$
$10000 = 11000 - 100r$
$-1000 = -100r$
$-1000/-100 = -100r/-100$
$10 = r$
$I = 3300-100*r$
$I = 3300-100*10$
$I = 3300-1000$
$I = 2300$
Private saving
$Y - T - C$
$10000 - T - 6000$
$4000 - 1500$
$2500$
Public saving
$T - G$
$T - 1700$
$1500 - 1700$
$-200$
Saving = investment
$S = I$
$S = 2300$