Question 772704
This is just like a concentration mixture problem in which the strength or concentration is units of Dollars per Kilogram, instead of "percent".


L = 9 dollars per kg, Thai
H = 16 dollars per kg, Indonesian
t= unknown price of mixture
M = 21 kg. mixture
U = 12 kg. of Thai
V = 9 kg. of Indonesian


Equations to Create the System:
{{{highlight((LU+HV)/M=t)}}} and {{{U+V=M}}}
but we only need the rational equation and t is already solved.


Just substitute the known values and compute t.
{{{highlight((9*12+16*9)/21=t)}}}