Please help :/ ill give brainlly -.-

2 50 mL bottles

Step-by-step explanation:

Find the cost per mL

55 / 80 mL =.6875 per mL

Now find the price of the buy one get one 1/2 off

45 + 1/2 (45) = 45+22.5=67.5

That will be for 50+50 mL

67.5 /100 ml =.675 per mL

The 100 mL is a better deal

Two 50 ml bottles.

Step-by-step explanation:

The 80 ml bottle costs £55. That means that you have to pay £55 / 80 per ml of perfume, which is £0.6875.

On the other hand, the 50 ml bottles cost £45. Since it is buy one get one half off, you can do 1.5 * £45 to get the price of both bottles. That would be £67.5 for 100 ml of perfume. You would pay £67.5 / 100 per ml of perfume, which is £0.675.

It is cheaper to get two bottles of 50 ml perfume, so that is the best value for the money.

Hope this helps!

thats not a system of equations, that is a solution