UPSC Government Jobs Exams

In how many ways can four children be made to stand in a line such that two of them, A and B are always together? [UPSC 2010 (CS-P)]
a) 6
b) 12
c) 18
d) 24

Read Solution (Total 1)

ABCD,ABDC,BACD,DCAB,DCBA,CDAB,CDBA,CABD,DABC,DBAC,CBAD,BADC
b) 12
8 years agoHelpfull: Yes(0) No(0)

UPSC Other Question

In an examination, there are three subjects A, B and C. A student has to pass in each subject. 20% students failed in A, 22% students failed in B and 16% failed in C. The total number of students passing the whole examination lies between [UPSC 2009(CS-P)]

1) 42% and 84%
2) 42% and 78%
3) 58% and 78%
4) 58% and 84% P, Q, R and S are four men. P is the oldest but not the poorest. R is the richest but not the oldest. Q is older than S but not than P or R. P is richer than Q but not than S. The four men can be ordered (descending) in respect of age and richness, respectively, as: [UPSC 2010 (CS-P)]
1) PQRS, RPSQ
2) PRQS, RSPQ
3) PRQS, RSQP
4) PRSQ, RSPQ