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Earn +20 ptsQ: Is 21 a triangular number
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Continue Learning about Math & Arithmetic
What is the 6th triangular number?
21
How do you find the 20Th triangular number?
The 20th triangular number is 20*21/2 = 210
Is 32 a triangular number?
32 is not a triangular number. The first few triangular numbers are 1, 3, 6, 10, 15, 21, 28, 36, 45, ...
How can sixth triangular number be 21?
Because it is ! The first 10 triangular numbers are... 1,3,6,10,15,21,28,36,45 & 55
Is 23 a triangle number?
No, 23 is not a triangular number. Here are a few examples of triangular numbers: 21, 28, 55, 45, 78 and 91.
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