1/2, 1/4, 1/8, 1/16, 1/32,1/64, 1/128 ....

1/2, 1/4, 1/8, 1/16, 1/32,1/64, 1/128 .... In the sequence above each term after after the first one-half the previous term. If x is the tenth term of the sequence, then x satisfies which of the following inequalities?

Quiz

Answer/Solution

0.000001 < x < 0.00001

Steps/Work

In the Sequence notice that the sequence is just the 1/(2^n) ...
so for 1st term=1/2^1=1/2
2nd term=1/(2^2)1/4, 3rd term=1/(2^3)=1/8 and so on...
Thus the 10th term will be 1/(2^10)=1/1024
Roughly, 1/1024 can be 1/1000=0.001 but since denominator is a bit more than 1000 therefore the actual value will be a bit less than 0.001.
thus the ans will lie btw. 0.000001 and 0.0001.(E)