Question 1097029
An arithmetic sequence is given by 5, 8, 11, ....
Write down the value of d. 
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d = 8-5 = 3
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Find 
I. u(100) = u1+99d = 5+99*3  
II. S(100) = (100/2)(5+5*99*3)
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Given that un = 1502, find the value of n.
u(n) = 5 + (n-1)d = 1502
(n-1)3 = 1497
n-1 = 499
n = 500
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Cheers,
Stan H.
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