Can someone explain why this is wrong or did my teacher just make a mistake

Which expression will have the same sum as 3_8 + 1/4?

What is the prime factorization of 23 ?me with this question

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 (%)