Question 800428
A rewording using all numbers as variables would be about like this:


|-------A candy distributor needs to mix a L% fat-content chocolate with a H% fat-content chocolate to create M kilograms of a T% fat-content chocolate. How many kilograms of each kind of chocolate must they use?---------|


Let u = kilograms of the L% fat content chocolate
Let v = kilograms of the H% fat content chocolate


Your equations would be these:
{{{highlight((Lu+Hv)/M=T)}}} and {{{highlight(u+v=M)}}}
Solve for u and v.