Addition and subtraction

What is the sum of all the digits in all the integers from one to one million?

Can you explain how this card trick works?

Five numbers added together in pairs produce: 0, 2, 4, 4, 6, 8, 9, 11, 13, 15 What are the five numbers?

Can you explain the strategy for winning this game with any target?

Jack's mum bought some candles to use on his birthday cakes and when his sister was born, she used them on her cakes too. Can you use the information to find out when Kate was born?

Can you arrange fifteen dominoes so that all the touching domino pieces add to 6 and the ends join up? Can you make all the joins add to 7?

What do the digits in the number fifteen add up to? How many other numbers have digits with the same total but no zeros?

Can you find two butterflies to go on each flower so that the numbers on each pair of butterflies adds to the number on their flower?

In your bank, you have three types of coins. The number of spots shows how much they are worth. Can you choose coins to exchange with the groups given to make the same total?

There were chews for 2p, mini eggs for 3p, Chocko bars for 5p and lollypops for 7p in the sweet shop. What could each of the children buy with their money?