Mock 2 question in BPP kit- 5th edition

I need help with a question in BPP pack 5th edition. It was included in the mock exam 2 Q1, a former PM paper 12/06 amended, called Wonderland.

Here’s my problem, in the (b) part of the question, we’re asked to prepare summarised results for different scenarios. we are given different variations for zoo revenues. In the solution, I cannot fathom how they derive their figures for increase by 10% esp, I thought my calculator was faulty but am beginning to wonder if it’s a typographical error but if not, how did they derive the figures.

Thanks for your help.