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anonymous
 4 years ago
find sum of the 1st 20 terms in the arithmetic series 5,8,11,14
anonymous
 4 years ago
find sum of the 1st 20 terms in the arithmetic series 5,8,11,14

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amistre64
 4 years ago
Best ResponseYou've already chosen the best response.1what do we add to get to each next term?

amistre64
 4 years ago
Best ResponseYou've already chosen the best response.1called a common difference

amistre64
 4 years ago
Best ResponseYou've already chosen the best response.13 is right :) so, Sn = n(first+last)/2 if i recall it right

amistre64
 4 years ago
Best ResponseYou've already chosen the best response.1to determine the 20th term is a20 = 5+3(19) = 62 62+5 = 67*20/2 = 670 ... if my math was good

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0Oh so it's 670? Thank you so so so much! wow thank you.

amistre64
 4 years ago
Best ResponseYou've already chosen the best response.1i hope so, id dbl chk with the wolf: sum (5+3(n1)) from 1 to 20

amistre64
 4 years ago
Best ResponseYou've already chosen the best response.1http://www.wolframalpha.com/input/?i=sum+%285%2B3%28n1%29%29+from+1+to+20

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0Can you help me with one more? Find the 7th term in the geometric sequence 4,20,11

amistre64
 4 years ago
Best ResponseYou've already chosen the best response.120/4 = our common ratio an = a1 * r^(n1) a7 = 4 * (20/5)^6

amistre64
 4 years ago
Best ResponseYou've already chosen the best response.1your 11 is bad there, is that a typo?

amistre64
 4 years ago
Best ResponseYou've already chosen the best response.1whew!! lol, then yeah; 4*5^6 should do it

amistre64
 4 years ago
Best ResponseYou've already chosen the best response.1i think its bigger than that; 5^4 = 25^2 = 625 alone

amistre64
 4 years ago
Best ResponseYou've already chosen the best response.1625*20 is what id end up with

amistre64
 4 years ago
Best ResponseYou've already chosen the best response.112500 perhaps? hard to do in the head :)

amistre64
 4 years ago
Best ResponseYou've already chosen the best response.1http://www.wolframalpha.com/input/?i=4*%285%5E6%29 almost had it :)

amistre64
 4 years ago
Best ResponseYou've already chosen the best response.1i left off the last *5 .... 12500*5=62500
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