Megan and Mundi went to a bar on Friday night. They had intended to split the bill for what they drank evenly, but Megan had forgotten her money, and thus Mundi paid for it all. Saturday morning, Megan wished to pay Mundi back. The two sat down to calculate the bill, and what they came up with was the following:

They couldn't remember how many beers Mundi had drank, but they concluded that it was one less than Megan had.

Megan had drank two less beers than the man they had met at the bar. This man's bill had come to $18.00 in total. He had drunk twice as many beers as Mundi.

Mundi had ordered a beer for Megan in honour of her birthday and so would pay for that.

Megan had ordered nachos with her beers. The nachos had cost $3.50

How much should Megan's bill come to?

The following piece of paper can be folded into a cube. Only one of the cubes depicted below is correct. Can you identify which one is correct?

Which number should come next in the following sequence?

2, 6, 3, 9, 6, 18, 15, 45, 42...