Question 436711: 1. find the 7th term in 16, 8, 4,....
2. Find the sum of the first 11 terms in the sequence 4,6,9...
3. What is the sum of the first 100 even numbers
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! 1. find the 7th term in 16, 8, 4,....
a = 7 ; r = (1/2)
a(7) = 7*(1/2)^6 = 7/64
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2. Find the sum of the first 11 terms in the sequence 4,6,9...
a = 4 ; r = 3/2
S(11) = 4[(3/2)^11-1 / (3/2)-1]
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S(11) = 4[85.50/0.5]
S(11) = 4[171] = 684
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3. What is the sum of the first 100 even numbers
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2+4+6+....+200
200+198+....+2
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Adding you get
2S = 100(1st+last)
S = 50*202
Sum = 10,100
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Cheers,
Stan H.
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