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🇰🇪 Kenya Billionaires (2025): Top 10 Richest Men in Kenya
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Wise Man
3 days agoSequences and Series continues.
Geometric Series: Find the sum of the first 4 terms of the sequence 2, 6, 18, 54, ...
Answer: The sum is 2 + 6 + 18 + 54 = 80.
Formula Examples
Arithmetic Sequence Formula: Find the 10th term of the sequence with first term 3 and common difference 2.
Answer: Using the formula an = a1 + (n-1)d, we get a10 = 3 + (10-1)2 = 21.
Geometric Sequence Formula: Find the 5th term of the sequence with first term 2 and common ratio 3.
Answer: Using the formula an = a1 • r^(n-1), we get T5 = 2 • 3^(5-1) = 162.
Word Problem Examples
Arithmetic Sequence Word Problem: A person saves $100 in the first month and increases the savings by $50 each month. How much will they save in the 6th month?
Answer: Using the arithmetic sequence formula, we get T6 = 100 + (6-1)50 = $350.
Geometric Sequence Word Problem: A population of bacteria doubles every hour. If there are 100 bacteria initially, how many will there be after 5 hours?
Answer: Using the geometric sequence formula, we get a5 = 100 * 2^(5-1) = 1600 bacteria.
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