Answers

2016-03-10T16:28:55+05:30
Multiply the common ratio to the first term to get the second term..Multiply the common ratio with the 2nd one to get 3rd and so on..
So using the information in the question ....The second term is 80x1/2 =40
and similarly the third term is 40x1/2=20
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2016-03-10T17:09:07+05:30
We know that the general term of an GP is-
tⁿ = a*(r) ⁿ⁻¹
So putting these vales
a=80
r=1/2

t² = 80*(1/2)²⁻¹
    = 80 * 1/2
     =40

t³ = 80*(1/2)³⁻¹
    = 80 * 1/4
     =20
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