There are 6 teachers A, B , C, D, E , F in a school. each teacher teaches 2 subjects, one compulsory other optional subject.
D's optional subject is history while 3 others have it as compulsory subject . E and F have physics as one of their subjects. F's compulsory subject is math which is optional subject of C and E. History and english are A's subjects but in terms of compulsory or optional subject they are reverse of those of D's. Chemistry is an optional subject of any one of them. there is only one female teacher in the school who has english as her compulsory subject.

76. What is C's compulsory subject?
a)history b)physics c)chemistry d)English

77. Who is the female member in the group?
a)A b)B c)C d)D

78. Who has some compulsory and optional subject, which are same as those of F's?
a)D b)B c)A d)C

79. Disregarding which is compulsory and which is optional subject, who has same two subject combination as F?
a)A b)B c)E d)D

80. Which group has history as compulsory subject?
a)A,C,D b)B,C,D c)C,D d) A,B,C

77) d
78 ) d
79 ) c
80 ) d

81 Which is valid sequence?
a) BACDEF b) FBACDE c) EDBACF d) ACFEDB

82 If A is placed at second position from the left , how many valid sequences are possible?
a) 6 b) 4 c) 9 d) 20

83 If C and D are placed adjacent to each other, how many valid sequence are possible?
a) 4 b) 2 c) 1 d) 0

84 Which is true ?
a) B may not occupy first position from left.
b) C can occupy 2'nd position from the left.
c) D can occupy 4'th,5'th, or 6'th position from the left.
d) F can occupy 1'st or 2'nd position from the left.

Q 85. If Mahim falls exactly halfway between Bandra and Dadar , what time should one reach Mahim station to catch this train ,if it is the only station in between ?
a) 10:54 ` b) 10:55 ` c) 10:56 d) 10:57

Q 86. If it takes just two minutes of travel from Borivili to Kandivli , at what time will the train reach Maland which is another 2 minutes away ?
a) 10:36 b)10:37 c)10:38 ` `d) Indeterminate

Q 87. If there are two stops between Andheri and Bandra , and the halting time is not changed , then what is the average running time between each station ?
a) 1 minute b)1(1/2) minute c) 2 minute d) 1(2/3) minute

Q 88. If church gate is exactly 7 minutes from Mumbai Central, then when does this train leave from church gate if it halts there for 6 minutes ?
a) 11:19 b) 11:20 c)11:22 `d)11:21

Q 89. Using the data in the above question , at what time will a similar train leave Borivli at 7:52 leave Churchgate again ?
a) 8:22 b) 8:42 ` c) 8:32 d) 8:30

Sol 85: - Accounting for the 1-minute halt at Bandra, the train leaves Bandra at 10:53 and Dadar is 7 minutes away (11:00 - 10:53), including 1-minute halt at Mahim. Since Mahim is at the half waypoint, the train will be there by (10:53 + 0:03) = 10:56.
Hence(c)

Sol 86: - It reaches Malad at è 10:32 + 0:02 + 0:01 + 0:02 = 10:37. .
Hence (b)

Sol 87: - Train starts from Andheri at 10:47 and reaches Bandra at 10:52.
Therefore difference = 5 minutes.
Deduct the 1-minute halt at each two stations
Therefore running time = 5 - (1 + 1) = 3 minutes
Therefore average running time = 3/3 = 1 minute.
Hence (a)

Sol 88: - Train leaves Mumbai Central at 11:09 (3 minutes halt). It then travels for 7 minutes, halts for 6 minutes before starting again è 13 minutes
Therefore it leaves Churchgate at 11:09 + 13 = 11:22.
Hence (c)

Sol 89: - the answer to the previous question was 11:22, thus the entire journey took 50 minutes.(11:22 - 10:32).
Thus, a train starting from Borivli at 7:52 will leave Churchgate at 7:52 + 0:50 = 8:42
Hence (b).