Private Savings

= Y-T-C $(10,000- $1500)- ($6000)= $2500
Public/ Government Savings=

= T-G ($1500-$1700= $-200
National/Total Savings= Y-C-G ($10,000- $6000)- ($1700)= $2300
*Note that national savings is also a sum of private+ public savings.
National Savings is equal to investment so that means
Investment= $2300
Equilbrium real interest rate- 3300-100R= 2300
R=10%