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Earn +20 ptsQ: What is the 81st triangle number?
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Continue Learning about Math & Arithmetic
Write the ordinal number of 81?
81st or eighty-first
Triangle number of 28?
28 is a triangle number. The 28th triangle number is 406.
What is the third triangle number?
The third triangle number is 6.
What is the fifth triangle number?
The fifth triangle number, known as T5 is 15.
Why is 10 called a triangular number?
A triangular number or triangle number counts the objects that can form an equilateral triangle. 10 objects can be formed into an equilateral triangle.
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