Foundation June 2023 Paper 1 Q16

16. Viola is arranging some paving slabs to make a path all around a rectangular pond.
Some of the slabs are grey and some are white.
There are no gaps between the slabs and no gaps between the slabs and the edge of the pond.
The diagram shows how she positions her first three slabs.

Diagram not drawn to scale

The ratio of grey slabs : white slabs is 3 : 1.

The pond is 2·5 metres by 3·5 metres.
Each slab is a square with side 50 centimetres.

A grey slab costs £5 and a white slab costs £6.

How much does it cost Viola to make her path? [6]