Whitney earns 15 dolllars for working 5 hours in a babysitting center. Then, the money she earns per hour is 3 dollars.
Amanda works as a carpenter and as a blacksmith. She earns $20 per hour as a carpenter and $25 dollar per hour as a blacksmith. Last week, Giselle worked both jobs for a total of 30 hours, and earned a total of $690dollar. How long did Giselle work as a carpenter last week, and how long did she work as a blacksmith?