+0  
 
0
87
1
avatar

What is the sum of all positive integers v for which lcm(v,20)=60.

Guest Jun 28, 2018
 #1
avatar+20153 
+1

What is the sum of all positive integers v for which lcm(v,20)=60.

 

\(\begin{array}{|r|r|r|r|c|} \hline v & \text{factor } v &\text{factor } 20 & \text{factor } 60 &\text{lcm}(v,20 ) \\ \hline 3 & {\color{red}3} & {\color{blue}2^2} \times {\color{green}5} & {\color{blue}2^2} \times {\color{red}3} \times {\color{green}5} & 60 \\ \hline 6 & {\color{red}3} \times 2 & {\color{blue}2^2} \times {\color{green}5} & {\color{blue}2^2} \times {\color{red}3} \times {\color{green}5} & 60 \\ \hline 15 & {\color{red}3} \times {\color{green}5} & {\color{blue}2^2} \times {\color{green}5} & {\color{blue}2^2} \times {\color{red}3} \times {\color{green}5} & 60 \\ \hline 30 & {\color{red}3} \times 2\times {\color{green}5} & {\color{blue}2^2} \times {\color{green}5} & {\color{blue}2^2} \times {\color{red}3} \times {\color{green}5} & 60 \\ \hline 12 & {\color{red}3} \times {\color{blue}2^2} & {\color{blue}2^2} \times {\color{green}5} & {\color{blue}2^2} \times {\color{red}3} \times {\color{green}5} & 60 \\ \hline 60 & {\color{red}3} \times {\color{blue}2^2} \times {\color{green}5} & {\color{blue}2^2} \times {\color{green}5} & {\color{blue}2^2} \times {\color{red}3} \times {\color{green}5} & 60 \\ \hline \text{sum } = 126 \\ \hline \end{array} \)

 

laugh

heureka  Jun 28, 2018

11 Online Users

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.