Give the step-by-step reasoning process and then the final answer. To earn money for her new computer, Tina sells handmade postcards. In a day, she can make 30 such postcards. For each postcard sold, Tina gets $5. How much money did Tina earn if she managed to sell all the postcards she made every day for 6 days?
Tina made postcards for 6 days, so she has made 6 days * 30 postcards / day = 180 postcards. For every postcard, Tina gets $5, so if she sold every card, she got 180 postcards * $5 / postcard = $900.
The final answer: 900.