Question 436711
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.