Question

What is the value of this proportion? 8/12 = 10/n

Answer 1

$\dfrac{8}{12}=\dfrac{10}{n}\\ \dfrac{2}{3}=\dfrac{10}{n}\\ 2n=30\\ n=15$

Answer 2

$\frac{8}{12}=\frac{10}{n}\ \ \ \ \ \ | cross\ multiplication\\\\ 8n=10*12\\\\ 8n=120\ \ \ \ | divide\ by\ 8\\\\ n=15$