Magic Maths PowerPoint Investigation : Playing Cards

Will your pupils think you have magical powers? Maybe!
From a pack of playing cards select the diamonds and clubs 2-9. Put them on the desk face down.
Get a student to come out and choose one of each suit. They can hold them up for the class to see.
Click the card to advance the slide.
A set of instructions appears and the class have to follow these to produce a number. Ask them to tell you the number.
Click on the magic wand (for the magic sound) to help you find their two cards.
There are 3 different puzzles each one is repeated making a total of 6.

To find the cards from the first 2 puzzles subtract 12 . The diamond is the 10s digit and the units is the club.
To find the next 2 puzzles, subtract 40. Again the 10s digit is the diamond and the units the club.
For the last 2 puzzles, subtract 70. The hundreds digit is the diamond and the units the club.

There is a separate worksheet for students to investigate how these puzzles work. Depending on the ability of the students algebra may be used.