Answer:
a4 =
5/9
Step-by-step explanation:
a1 = 15 , r =
1/3
, a4 =?
Explanation:
To find a4 we use formula
an = a1 · r
n−1
In this example we have a1 = 15 , r =
1/3
, n = 4. After substituting these values to above
formula, we obtain:
an = a1 · r
n−1
a4 = 15 ·
1
3
4−1
a4 = 15 ·
1
27
a4 =
5
9
