GCSE Maths from Scratch 8.04 Grouped Tables

[marsh]

I don't quite understand the notation used, though I do understand the concept of what you're saying. If ≤ means 'less than or equal to' and < means 'less than', then why would x be inbetween these?

For your first example I can't see this meaning anything other than 'x is less than or equal to 8.0 and less than 8.5', although I do know that what you mean is 'x is greater than or equal to 8.0 but strictly less than 8.5.'

I just don't undertstand why we're using the 'less than or equal to' symbol (≤) when what we're trying to say is that x is more than or equal to 8.0. Sorry if my confusion was confusing.