Maths Challenge – Can you make fifteen?
Tim had nine cards, each with a different number from 1 to 9 on it.
He put the cards into three piles so that the total in each pile was 15.
Hints and Tips
- Make your own set of 1 to 9 cards to help you.
- Think about the total of the whole set of cards.
- You don’t have to have the same amount of cards in each pile. Only the total of each pile should be the same.
- Use attempts that don’t work to help you try again!
Bronze: 7+8=15 6+5+4=15 1+2+3+9=15
Silver: 7+8=15 6+5+3+1=15 9+2+4=15
Gold: 7+8=15 2+4+5+3+1=15 9+6=15
All you have to do is exchange 1 number for 2 numbers with the same quantity
bronze 5+4+6
9+4+2
5+3+7
9+1+5
2+6+7
2+8+5
Hi George, well done for your effort. What will the 3 pile of cards be if each card is used once?
Well done George. Could you challenge yourself with silver and see if you could find another way?
silver
you could multiply them 3×5=15
2×5+5=15
6+9=15
4+5+6
8+7=15
1+5+9=15
8+7+1_1=15
1+6+8=15
2+5+8=15
Well done for finding lots of ways to make 15 using the cards. What could the 3 piles be? Don’t forget that each card will be used once.
Great effort Simar. You have found 3 ways to do this. Are there definitely no more?
1+2+3+9=15
7+8=15
5+4+6=15
6+9=15
9+4+2=15
1+5+3+6=15
Well done Hassan, how could you know you’ve found all the possibilities?