Addition and subtraction

How far apart are the first and last bus stops in this bus route?

What were the maximum and minimum temperatures recorded in my max/min thermometer?

This task follows on from Build it Up and takes the ideas into three dimensions!

Can you explain how this card trick works?

A combination mechanism for a safe comprises thirty-two tumblers numbered from one to thirty-two in such a way that the numbers in each wheel total 132... Could you open the safe?

There are exactly 3 ways to add 4 odd numbers to get 10. Find all the ways of adding 8 odd numbers to get 20. To be sure of getting all the solutions you will need to be systematic. What about a total of 15 with 6 odd numbers?

In the following sum the letters A, B, C, D, E and F stand for six distinct digits. Find all the ways of replacing the letters with digits so that the arithmetic is correct.

Replace each letter with a digit to make this addition correct.

Try adding together the dates of all the days in one week. Now multiply the first date by 7 and add 21. Can you explain what happens?

Can you substitute numbers for the letters in these sums?