Examine why they work ? Write down any three digit number (for example

1.	Examine why they work ? Write down any three digit number (for example, 425). Make a six digit number by repeating these digits in the same order 425425. Your new number is divisible by 7, 11 and 13.
Answer» Let a three digit number be xyz. Repeat the digit = xyzxyz = xyz × (1001) = xyz × (7 × 11 × 13) Hence the given conjecture is true.

Examine why they work ? Write down any three digit number (for example, 425). Make a six digit number by repeating these digits in the same order 425425. Your new number is divisible by 7, 11 and 13.

Answer»

Let a three digit number be xyz.

Repeat the digit = xyzxyz

= xyz × (1001)

= xyz × (7 × 11 × 13)

Hence the given conjecture is true.