A local hamburger shop sold a combined total of hamburgers and cheeseburgers on Thursday. There were more cheeseburgers sold than hamburgers. How many hamburgers were sold on Thursday?

Acompany that manufactures and sells guitars made changes in their product range. from the start they had 20 models. then they reduced the number of models to 15. as a result, the company enjoyed a 10% increase in turnover. - how much did the stock level change? in (%)