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Please help meee oh please

Please help meee oh please-example-1
User Yardboy
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1 Answer

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Collecting the data of this P.G., comes:

The 1st term
a_(1) = 648
The 2nd term
a_(2) = 216

The ratio

r = \frac {a2}{a1}
The number of terms n = 8

The 8th term

a_(8) = ?

The value of ratio, we have:
The ratio
r = \frac {a2}{a1}

r = \frac {a2}{a1} = (216)/(648) (/6)/(/6) = (36)/(108) (/6)/(/6) = (6)/(18) (/6)/(/6) \to\:r= (1)/(3)

Applying the general term formula of P.G., comes:

a_(n) = a_(1) *r^(n-1)

a_(8) = 648 * ((1)/(3)) ^(8-1)

a_(8) = 648 * ((1)/(3)) ^(7)

a_(8) = 648 * (1)/(3^7)

a_(8) = 648 * (1)/(2187)

a_(8) = (648)/(2187)
Simplify


a_(8) = (648)/(2187) (/9)/(/9) = (72)/(243) (/9)/(/9) \to\: \boxed{\boxed{a_(8) = (8)/(27)}}\end{array}}\qquad\quad\checkmark

Answer:

\boxed{\boxed{a_(8) = (8)/(27)}}



User Jansenmaarten
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