0 reads0 ratings0 helpful
A staircase figure has (1275) blocks, and the (r)th row has (r) blocks. What is the number of rows?
Advertisement
Answer and explanation
Correct answer: (50)
Total blocks are (S_r=1275), and (S_{50}=1275), so there are (50) rows. In such figures, the total objects form a triangular number.
Frequently asked questions
What is the correct answer to this question?
(50)
Why is this the correct answer?
Total blocks are (S_r=1275), and (S_{50}=1275), so there are (50) rows. In such figures, the total objects form a triangular number.
Which subject and chapter does this question cover?
This is a Class 9 Mathematics question. Chapter: Sequences and Progressions. Topic: Sum of first n natural numbers.
Student feedback
Was this question useful?
Was this question useful?
👍 0 Helpful 👎 0 Not helpful
Difficulty
Easy0%
Medium0%
Hard0%
Was the explanation clear?
Yes 0% No 0%
0 responsesStudent Reviews
No published reviews yet.
Advertisement