For every integer k from 1 to 10, inclusive, the kth term of a certain sequence is given by (-1)^(k+1) * 1/2^k. If T is the sum of the first 10 terms in the sequence, then T is
A) greater than 2
B) between 1 and 2
C) between 1/2 and 1
D) between 1/4 and 1/2
E) less than 1/4
(in the 1/2^k only the 2 is raised to the power of k not 1/2).
Also:
An investment of d dollars at k percent simple annual interest yields $600 interest over a 2 year period. In terms of d, what dollar amount invested at the same rate will yield $2,400 interest over a 3-year period?
A) 2d/3
B) 3d/4
C) 4d/3
D) 3d/2
E) 8d/3
If you can please try to break down the steps as I may not be able to make the leaps. Thanks in advance.
A) greater than 2
B) between 1 and 2
C) between 1/2 and 1
D) between 1/4 and 1/2
E) less than 1/4
(in the 1/2^k only the 2 is raised to the power of k not 1/2).
Also:
An investment of d dollars at k percent simple annual interest yields $600 interest over a 2 year period. In terms of d, what dollar amount invested at the same rate will yield $2,400 interest over a 3-year period?
A) 2d/3
B) 3d/4
C) 4d/3
D) 3d/2
E) 8d/3
If you can please try to break down the steps as I may not be able to make the leaps. Thanks in advance.












