Question 1011921
x, how many grams of the P500 metal.


{{{500x+20*320=(x+20)*400}}}


Look through and study for clear understanding:
<a href="http://www.algebra.com/my/Two-Part-Mixture-with-one-material-quantity-unknown.lesson?content_action=show_dev">One quantity unknown but other known for two-part mixture</a>