Answer:
Step-by-step explanation:
Now sum of infinite series is
a
1
−
r
and if first three term are removed, fourth term becomes the first term i.e. first term becomes
a
r
3
and
sum of infinite series becomes
a
r
3
1
−
r
As
a
1
−
r
=
27
×
a
r
3
1
−
r
27
r
3
=
1
or
r
3
=
1
27
and
r
=
1
3
and hence
Common ratio is
1
3