Jawabanmu

2014-03-03T15:54:17+07:00
B = y-x/ k-1
      21 - 16 / 4+1
       5/5 = 1

jumlah
41 = 16 + (n-1) . 1
41-16 = n-1
25 = n- 1
n =16

S26 = 26/2 ( 16 + 21)
          13 (37) = hitung sendiri
Jawaban paling cerdas!
2014-03-03T17:36:05+07:00
B = ( Un - U1 ) / ( k + 1 )

b = ( 41 - 16 ) / ( 4 + 1 ) = 25 /5 = 5
maka beda = 5

n = ( k + 2 ) = 4 + 2 = 6 .

Sn = n/2 x ( U1 + Un )
     = 6 / 2 x ( 41 + 16 )
     = 3 x 57 = 171 ...


Ini jawaban ane gan :)

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