Please help me with this on the picture

Answer:
5, 7
Step-by-step explanation:
The mode of the numbers is 5, which means that 5 should be the most common card (highest frequency). Therefore the cards should have at least one more 5 among them.
Considering that 5 is one of the hidden cards and x is the other,
• Using the equation for the mean:
[tex]mean = \frac{sum \space\ \space\ of \space\ \space\ numbers}{number \space\ \space\ of \space\ \space\ numbers}[/tex]
[tex]6 = \frac{4+5+ 9 + 5 + x}{5}[/tex]
⇒ [tex]30=23 + x[/tex]
⇒ [tex]x = 7[/tex]
This means 5 and 7 are the hidden cards.