<PRE><B>Question 998953</B>
 a shop mixes 30 kg of brand a which costs $32 per kg with 20 kg of Brand b tea which cost $35 per kg .
 he sells mixture at$ 40 per kg. find his profit or loss as a percentage of his cost. 
:
Find the original cost of the ingredients
32(30) = 960
35(20) = 700
--------------
total C: $1660
:
Find the price of the resulting mixture
40(30+20) = $2000
find the profit
2000 - 1660 = $340
:
Find the profit as a percentage of his cost
{{{340/1660}}} * 100 = 20.48%</PRE>