There are 5 starters, k k\,k main courses and x x\,x desserts in a restaurant.
Riley says there are 130 different ways of choosing a starter, a main course and a dessert.
Find x x\,x in terms of kkk, and hence decide when Riley could be correct.
You must show your working.
181 exam-style questions on CCEA GCSE Maths The Product Rule for Counting. Each one has a worked solution and a mark scheme showing where the marks go.