Answer:
The amount of coffee A is 4 pounds.
Explanation:
Let, the amount of coffee A is x pound
So the amount of coffee B = 12 —x pound
Cost of A = x $\times$ 100 = 100 x Tk.
Cost ot‘B =(12—x) x 70 =(12-x) 70 Tk
Cost of mixture = 12 x 80 = 960 TK
100x+(12-x)70 = 960
=> 100x + 840 – 70= 960
=> 30x = 960 – 840 = 120
x = $\frac{120}{30}$ = 4
