Question

Question is attached ​

Answer 1

• Question 62. B) 8
• Question 63. D) 4/3

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Question 62

From the series we can observe:

• The first term of the GP is t = 1/2,
• The common ratio is r = - 1/2,
• The nth term is - 1/256.

Use the nth term equation to find the value of n:

• 
  `t_n=t*r^(n-1)`

Apply this to the last term and solve for n:

• 
  `-1/256=1/2*(-1/2)^(n-1)`
• 
  `-1/128= (-1/2)^(n-1)`
• 
  `(-1/2)^7=(-1/2)^(n-1)`
• 
  `n-1=7`
• 
  `n=8`

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Question 62

Given

Infinite sequence:

• 2, - 1, 1/2, - 1/4, 1/8, ...

It has:

• t = 2, r = - 1/2

Find the sum of terms:

• S = t / ( 1 - r)
• S = 2 /( 1 + 1/2) = 2 / (3/2) = 4/3

Correct choice is D.