What number comes next in this sequence:

3 24 102 312 777 ==?==

At what distance from the earth it is possible to see exactly 1/3 of the earth's surface?

What are the next two numbers in this sequence:

202 122 232 425 262 728 ==?== ==?==

I once cashed a cheque at the bank. I had spent £1.20 before I realised the bank clerk had made a mistake. He had transposed the pounds with the pence. I now had exactly 7 times the value of the original cheque. What was the original cheque's value?

What letter comes next in this sequence:

A S D F G H ==?==