Same chapter3 marksDifficulty: Medium
The third term of a geometric progression is 12 and the sixth term is 96. Find the first term and the common ratio.
Sequence and Series
3 marksDifficulty: Medium
Find the sum of the first 20 odd natural numbers.
Original Khojo Papers practice question — not from a past board paper.
Answer
400
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
The sum of the first n odd numbers is n2, so for n = 20 it is 400.
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