## Thursday, 26 January 2017

### Calculator Skills 02: Calculator Talks!

Let's key the digits 1, 2, 3, 4, 5, 6, 7, 8, 9, 0 into the calculator. Look at what's displayed on the calculator output screen. Turn the calculator upside-down. Do they look like any letters in the alphabet?

For example: The digit 0 becomes O, 1 becomes I, 2 becomes Z, 3 becomes E, 4 becomes h, 5 becomes S, 6 becomes g, 7 becomes L, 8 becomes B, and 9 becomes G.

Let's try the following:
• enter 6.2
• multiply this by itself
• divide by 50
Turn the calculator upside down, and you have a friendly greeting!

Let's see what we have for breakfast:
• multiply this by 1000
• divide the result by 6
• throw away the part to the right of the decimal (what is the TECHNICAL term for this???)
• subtract 3 from the result. Mmm! Delicious!
• But be sure to throw the ( 68 x 68 - 7 ) x 5 x 5 x 5 + 220 in the trash!
Let's see if you could figure out the secret code below :)
• Does the ( 19 + 19 - 1 ) x 19 + 2 x 3 x 5 have (47 x 47 + 10 x 10 ) x 5 x 5 - 3 x 3 or (47 x 10 + 47 x 10 + 47 x 10 + 47 x 10 - 1) x 3 ? or lay 7 x (800 + 9)?
• Is there one in your neighbourhood 1 / 50 ?
• What about the 2 x 13 x 13 ?
• Or the 3 x 3 x 3 x 3 x 101 - 3000?
• The (50 x 50 x 3 + 1) x 6 - (50 x 50 x 4)?

(Of course, the plural of (50 x 50 x 3 + 1) x 6 - (50 x 50 x 4) is (8 - 1) x 8 x ( 8 x ( 8 x (8 + 1 + 1) - 1 ) - 1 ), isn't it.)

Now, create a secret code that and post it in the Padlet!

Each unique expression resulting in word will worth...

• Expressions involving +, -, x, ÷ will gain the 3 points
• Expressions involving squares, cubes and roots will gain 1 bonus point (on top of 3 points)
• Expressions phrase made up of 3 or more words will gain 10 points
Remember to add your name and group number to the title of the post.

The above is an interesting way to use arithmetic to 'code' secret messages.

Do you know...

Source: https://www-old.newton.ac.uk/wmy2kposters/booklet/