Answer:
Step-by-step explanation:
80 ml bottle for 55 : 55/80= 11/6=0.6875
50 ml bottle the price ( buy one get half price off the second one) :
45+(45*50%)=67.5 for two bottles
price per ml for 50ml bottle: 67.5/100=0.675
comparing prices : 0.675 is less than 0.6875
it is better to buy 50 ml bottle
not a big difference
