Answer:
5 tins of paint
Step-by-step explanation:
If the painter has calculated that he will need 4.2 tins of paint, he will need to purchase at least 5 tins of paint to ensure he has enough to cover his needs. It's always advisable to round up when dealing with quantities like paint, as having a bit extra is better than running out during a project. Therefore, the painter should buy 5 tins of paint.
