The total amount of money raised from friends contribution is 40/100*$10000 = $<<40/100*10000=4000>>4000
Minus his friend's contribution, the 40th president has raised $10000-$4000 = $6000
The family raised 30/100*$6000 = $<<30/100*6000=1800>>1800
If the family raised $1800, the savings the 40th president had for the campaign is $6000-$1800 = $4200
#### 4200