Resources tagged with Triangle numbers similar to Slick Summing:
Other tags that relate to Slick Summing
Arithmetic sequence. Making and proving conjectures. Summation of series. Triangle numbers. Learning mathematics. Mathematical induction. Pedagogy. Video. Mathematical reasoning & proof. Geometric sequence.There are 15 results
Broad Topics > Numbers and the Number System > Triangle numbers
Slick Summing
Age 14 to 16 Challenge Level:
Watch the video to see how Charlie works out the sum. Can you adapt his method?
Reasonable Algebra
Age 14 to 16 Challenge Level:
Use algebra to reason why 16 and 32 are impossible to create as the sum of consecutive numbers.
Mystic Rose
Age 14 to 16 Challenge Level:
Use the animation to help you work out how many lines are needed to draw mystic roses of different sizes.
Iff
Age 14 to 18 Challenge Level:
Take a triangular number, multiply it by 8 and add 1. What is special about your answer? Can you prove it?
Triangular Triples
Age 11 to 14 Challenge Level:
Show that 8778, 10296 and 13530 are three triangular numbers and that they form a Pythagorean triple.
Route to Infinity
Age 11 to 14 Challenge Level:
Can you describe this route to infinity? Where will the arrows take you next?
Handshakes
Age 11 to 14 Challenge Level:
Can you find an efficient method to work out how many handshakes there would be if hundreds of people met?
Human Food
Age 7 to 14 Challenge Level:
Sam displays cans in 3 triangular stacks. With the same number he could make one large triangular stack or stack them all in a square based pyramid. How many cans are there how were they arranged?
Sam Again
Age 11 to 14 Challenge Level:
Here is a collection of puzzles about Sam's shop sent in by club members. Perhaps you can make up more puzzles, find formulas or find general methods.
Picturing Triangular Numbers
Age 11 to 14 Challenge Level:
Triangular numbers can be represented by a triangular array of squares. What do you notice about the sum of identical triangle numbers?
Take Ten Sticks
Age 11 to 16 Challenge Level:
Take ten sticks in heaps any way you like. Make a new heap using one from each of the heaps. By repeating that process could the arrangement 7 - 1 - 1 - 1 ever turn up, except by starting with it?
Triangle Numbers
Age 11 to 14 Challenge Level:
Take a look at the multiplication square. The first eleven triangle numbers have been identified. Can you see a pattern? Does the pattern continue?
Satisfying Statements
Age 11 to 14 Challenge Level:
Can you find any two-digit numbers that satisfy all of these statements?
Forgotten Number
Age 11 to 14 Challenge Level:
I have forgotten the number of the combination of the lock on my briefcase. I did have a method for remembering it...
Factors and Multiples Puzzle
Age 11 to 14 Challenge Level:
Using your knowledge of the properties of numbers, can you fill all the squares on the board?
NRICH is part of the family of activities in the Millennium Mathematics Project.