Answer: The number is 15.
Step-by-step explanation: We are given a certain number we don't know about. Since it's value is unknown it is a variable. We'll call this variable "x". That number, x, is divided by 3, and then 3 was added to x to make 8. So then if x = 15, then dividing it by 3 would make 5, and adding 3 to that would make 8.
Another way to solve this, or check your work, is to work the problem out in reverse. Starting with the number 8, subtract 3 and then multiply that number by 3. This will give you the number 15. Which shows that the answer is correct.
![((15)/(3)) + 3 = x](https://img.qammunity.org/2022/formulas/mathematics/high-school/l513xp11c24lw4x4vvrpbzhpy2cr029tx8.png)
![5+3= x](https://img.qammunity.org/2022/formulas/mathematics/high-school/f0oyn4ue4pig71eyodz16l242o3ox64neh.png)
![8=x](https://img.qammunity.org/2022/formulas/mathematics/college/rw3qnemkt4gv4urxj4h516nko799bbahuk.png)
![x=8](https://img.qammunity.org/2022/formulas/mathematics/college/z69van35jyyoywr52whs11c9lrjflb3rp3.png)
![3(8-3) = x](https://img.qammunity.org/2022/formulas/mathematics/high-school/cxsug7fy7jqqu4v26hly2zw6buu7h79hdv.png)
or
![24 - 9 = x](https://img.qammunity.org/2022/formulas/mathematics/high-school/hkig936cc6v1x2zfwl89evo6r27ngxpf4d.png)
![15 = x](https://img.qammunity.org/2022/formulas/mathematics/high-school/89u6jcfevjieeae61xvae0jyoh21xfz3kj.png)
![x=15](https://img.qammunity.org/2022/formulas/mathematics/high-school/772soggszwrdwst60x4slafs3txdxb7skt.png)
Thus the number is 15. Hope this helps, and have a great day!