CHALLENGE
These challenges are tricky - you don't have to do them!
If you have a go - Well Done!
If you need a clue scroll down the page.
The questions below test your knowledge of multiples and involve remainders.
1. I'm thinking of a number that is 1 more than a multiple of 7.
My friend is thinking of a number that is 1 more than a multiple of 4.
Could we be thinking of the same number?
2. I'm thinking of a number that is 3 more than a multiple of 5.
My friend is thinking of a number that is 8 more than a multiple of 10.
Could we be thinking of the same number?
3. I'm thinking of a number that is 3 more than a multiple of 6.
My friend is thinking of a number that is 2 more than a multiple of 4.
Could we be thinking of the same number?
How to solve them
PURPLE PROBLEMS
1. Using lowest common multiples again : multiply 7 by 4 to get 28 add 1 is 29.
Both people could think of 29.
So the friend thinks of 28 + 1 as one more than a multiple of 4,
and the other person thinks of 28 + 1 as one more than a multiple of 7.
both have thought of the same answer.
2. Write down multiples of 5 and add 3 to them
Write down the multiples of 10 and add 8 to them.
Some of the numbers will be the same because 8 more than a multiple of 10 is the same as 3 more than a multiple of 5 which ends in 5.
3. Write down multiples of 6 and add 3 to them
Write down the multiples of 4 and add 2 to them.
You should notice that none of the numbers are the same.
No, you can not have been thinking of the same number because 3 more than a multiple of 6 is always an odd number and 2 more than a multiple of 4 is always an even. number