1. **State the problem:** We need to find the number of child tickets sold at the movie theatre given that child tickets cost $6.30, adult tickets cost $9.40, three times as many adult tickets as child tickets were sold, and total sales were $1035.00. 2. **Define variables:** Let $x$ be the number of child tickets sold. 3. **Express adult tickets in terms of child tickets:** Since three times as many adult tickets were sold, adult tickets sold = $3x$. 4. **Write the total sales equation:** Total sales = (price per child ticket) \times (number of child tickets) + (price per adult ticket) \times (number of adult tickets) $$6.30x + 9.40(3x) = 1035$$ 5. **Simplify the equation:** $$6.30x + 28.20x = 1035$$ $$34.50x = 1035$$ 6. **Solve for $x$:** $$x = \frac{1035}{34.50}$$ 7. **Calculate the value:** $$x = 30$$ **Answer:** The number of child tickets sold that day is **30**.