More mathematical mysteries

Write down a three-digit number Change the order of the digits to get a different number Find the difference between the two three digit numbers Follow the rest of the instructions then try to explain why this works.

Age

11 to 14

Challenge level

Exploring and noticing Working systematically Conjecturing and generalising Visualising and representing Reasoning, convincing and proving

Being curious Being resourceful Being resilient Being collaborative

Problem

Write down a three-digit number

Change the order of the digits to get a different number

Find the difference between the two three digit numbers

Add together the digits of your answer. If you arrive at a two-digit answer, add the two digits to reduce your answer to a single digit answer

Subtract $5$ from the number you have

Find that equivalent number letter in the alphabet (1=A, 2=B etc.)

Name a country that begins with letter

Using the second letter of the name of the country that you chose, name a jungle animal that starts with that letter.

Name the colour of that animal.

Using the final letter of the name of the country that you chose, name a different animal that starts with that letter.

Name a fruit that starts with the last letter of that animal's name.

Did you end up with orange or apple?

How did I know?

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