The packet is better value for money is a 125 g packet of beans which costs £0.36.
The better value for money of packet of beans can be calculated as follows?
The first step we can check on the first packet value for money by calculating the costs of 1 g of beans as follows :

The second step we can check on the second packet value for money by calculating the costs of 1 g of beans as follows :

Hence, the better value for money between those two packet of beans is the second packet of beans which given by 125 g and costs £0.36.