1. Which one set of letters when sequentially placed at the gaps in the given letter series shall complete it ?
aab _ aa _ bbb _ aaa _ bbba
a) abba
b) baab
c) aaab
d) abab
Explanation: The series is,
aabb / aaabbb / aaaabbbb / a.
Thus letters are repeated twice, then thrice then four times and so on.
2. _ bcc _ ac _ aabb _ ab _ cc.
a) aabca
b) abaca
c) bacab
d) bacaa
Explanation: The series is,
bbccaa / ccaabb / aabbcc.
The pairs of the letters are moving in cyclic order.
3. b _ ccacca _ ba _ bbc _ bc _ a.
a) baabc
b) abaaa
c) acbca
d) bacab
Explanation: The series is,
bbcca / ccaab / aabbc / bbcca.
4.Which one set of letters when sequentially placed at the gaps in the given letter series shall complete it ?
_ stt _ tt _ tts _
a) tsts
b) ttst
c) sstt
d) tsst
Explanation: The series is tst/tst/tst/tst. Thus, the pattern 'tst' is repeated.
5. Which one set of letters when sequentially placed at the gaps in the given letter series shall complete it ?
gfe _ ig _ eii _ fei _ gf_ ii
a) eifgi
b) figie
c) ifgie
d) ifige
Explanation: The series is gfeii/gfeii/gfeii/gfeii. Thus, the pattern 'gfeii' is repeated.
6. Choose the correct order of the given alternative : _ stt _ tt _ tts _
a) tsts
b) ttst
c) sstt
d) tsst
Explanation: The series is tst/tst/tst/tst. Thus, the pattern 'tst' is repeated.
7. Choose the correct order of the given alternative : _ nmmn _ mmnn _ mnnm _
a) nmmn
b) mnnm
c) nnmm
d) nmnm
Explanation: The series is nnmm/nnmm/nnmm/nnmm. Thus, the pattern 'nnmm' is repeated.
8. Choose the correct order of the given alternative : a _ bd _ da _ dbc _ b _ dc
a) aabbc
b) bbcca
c) caabb
d) ccbaa
Explanation: The series is acbd/cdab/dbca/badc. Clearly, each group consists of letters of the previous group in the order - second, forth, fifth, third..
9. Choose the correct order of the given alternative : a _ bc _ a _ bcda _ ccd _ bcd _
a) abddbd
b) acbdbb
c) adbbad
d) adbcad
Explanation: The series is aabcd/abbcd/abccd/abcdd.
10. Choose the correct order of the given alternative : a _ bb _ baa _ bbb _ aa _
a) aabba
b) bbaab
c) abaaa
d) baabb
Explanation: The series is aabbbb/aaabbb/aaaa. At each step, the number of a's increases by one; while the number of b's decreases by one.