One liter of shampoo cost £8.20. What is the cost of 325ml?

£ 2.67

Step-by-step explanation:

1 liter = 1000 ml

Cost of 1000 ml shampoo =  £8.20

Cost of 1 ml shampoo =

Cost of 325 ml shampoo =

                                         = 2.665

                                        = £ 2.67

option 1 is correct.

step-by-step explanation:

y varies inversely with x and constant of variation is 4

the equation will be:

y = k/x

where k =4 so,

y = 4/x

if we put values of x of option 1 in the above equation and find values of y

y = 4/-2 => y =-2

y = 4/-1 => y = -4

y = 4/1 => y = 4

y = 4/2 => y =2

so, all the values of x and y are correct.

if we put values of x given in other options and find value of y we cannot find whole table satisfying the equation.

hence option 1 is correct.