Harry's birthday was three weeks after the closing of the school. His three friends decided to contribute an equal amount of money to throw him a party. Harry added $30 to the contribution, making the total contribution three times as much as Harry contributed. Calculate the total amount of money that each of Harry's friends contributed.
If the total contribution was three times as much as Harry contributed, and Harry contributed $30, the total contribution was 3*$30=$<<3*30=90>>90
Since Harry contributed $30, his three friends together contributed $90-$30=$60
Since the three friends were contributing an equal amount, each friend contributed $60/3=$<<60/3=20>>20.
#### 20