Question 763032
What would be the price of the mixture of these teas, if u= kg of P24 type and v = kg of the P34 type:
{{{24u+34v}}} P units  for {{{(u+v)}}} kilograms.
The 1 kg unit cost is {{{(24u+34v)/(u+v)}}} P per kg.


Undo that 20% profit to know the cost per kg for the mixture originally.
{{{(1/1.20)(36)=30}}} P per kg is this original mixture price or cost.


Original mixture price: {{{(24u+34v)/(u+v)=30}}}
And we could have assumed the original mixing were based on forming a 1 kilogram mixture, so that {{{u+v=1}}}


Use that sum relationship as substitution to the "30" equation and divide left & right by 2 to simplify that "30" so you have this system to solve:

{{{(12u+17v)/1=30}}} and {{{u+v=1}}}
{{{highlight(12u+17v=30)}}} and {{{highlight(u+v=1)}}}
Now just solve for u and v.