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The first term of a geometric sequence is 40, and the common ratio is 0.5. What is the 5th term of the sequence?

1 Answer

Answer:

#T_5 = 2.5#

Explanation:

The #n^(th)# term of a geometric progression can be determined by using the formula:

#color(blue)(T_n = ar^(n-1))#
where: a = first term and r = common ratio

Substitute the given values of first term and common ratio into the formula:

#T_n = ar^(n-1)#
#T_5 = (40)(0.5)^(5-1)#
#T_5 = (40)(0.5)^(4)#
#T_5 = (40)(0.0625)#
#T_5 = 2.5#