Coffee A normally costs Tk.100 per lb. It is mixed with coffee B, which normally costs Tk.70 per lb, to from a mixture that c...

Coffee A normally costs Tk.100 per lb. It is mixed with coffee B, which normally costs Tk.70 per lb, to from a mixture that costs Tk.88 per lb. If there are 10 lbs of the mix, how many pounds of coffee A is used in the mixture?