+0  
 
0
438
2
avatar

the average of 3 numbers is 7. Two of the numbers are 8 and 9. What is the 3rd?

Guest May 27, 2015

Best Answer 

 #1
avatar
+10

$${\frac{\left({\mathtt{x}}{\mathtt{\,\small\textbf+\,}}{\mathtt{8}}{\mathtt{\,\small\textbf+\,}}{\mathtt{9}}\right)}{{\mathtt{3}}}} = {\mathtt{7}}$$

$${\mathtt{x}}{\mathtt{\,\small\textbf+\,}}{\mathtt{8}}{\mathtt{\,\small\textbf+\,}}{\mathtt{9}} = {\mathtt{21}}$$

$${\mathtt{x}} = {\mathtt{21}}{\mathtt{\,-\,}}{\mathtt{8}}{\mathtt{\,-\,}}{\mathtt{9}}$$

$${\mathtt{x}} = {\mathtt{4}}$$

Guest May 27, 2015
 #1
avatar
+10
Best Answer

$${\frac{\left({\mathtt{x}}{\mathtt{\,\small\textbf+\,}}{\mathtt{8}}{\mathtt{\,\small\textbf+\,}}{\mathtt{9}}\right)}{{\mathtt{3}}}} = {\mathtt{7}}$$

$${\mathtt{x}}{\mathtt{\,\small\textbf+\,}}{\mathtt{8}}{\mathtt{\,\small\textbf+\,}}{\mathtt{9}} = {\mathtt{21}}$$

$${\mathtt{x}} = {\mathtt{21}}{\mathtt{\,-\,}}{\mathtt{8}}{\mathtt{\,-\,}}{\mathtt{9}}$$

$${\mathtt{x}} = {\mathtt{4}}$$

Guest May 27, 2015
 #2
avatar+92624 
0

Nice answer anon :))

Melody  May 28, 2015

11 Online Users

avatar
avatar
avatar
avatar

New Privacy Policy

We use cookies to personalise content and advertisements and to analyse access to our website. Furthermore, our partners for online advertising receive information about your use of our website.
For more information: our cookie policy and privacy policy.