Question: The average mark obtained by 22 candidates in an examination is 49. The average of the first ten is 55 while the last eleven is 40 .The marks obtained by the 11th candidate is ?
Options:
(A) 22
(B) 0
(C) 99
(D) 88
(E) 66
Answer: It is clear that 22 x 49 = 10 x 55 + K + 11 x 40 K = 88
The answer is (D).

Question: The difference between the place value and the face value of 6 in the numeral 856973 is
Options:
(A) 5994
(B) 6973
(C) 973
(D) 1000
(E) 7000
Answer: (Place value of 6) - (Face value of 6) = (6000 - 6) = 5994
The answer is (A).

Question: The speed of a boat in upstream is 80 kmph and the speed of the boat downstream is 100 kmph. Find the speed of the boat in still water and the speed of the stream?
Options:
(A) 90, 10 kmph
(B) 35, 27 kmph
(C) 50, 60 kmph
(D) 45, 55 kmph
(E) 45, 65 kmph
Answer: Speed of the boat in still water = (80+100)/2 = 90 kmph. Speed of the stream = (100-80)/2 = 10 kmph
The answer is (A).

Question: P can do a work in 24 days. Q can do the samework in 9 days & R can do the same work in 12 days. Q & R start the work and leave after 3 days. P finishes the remaining work in how many days.
Options:
(A) 8
(B) 10
(C) 14
(D) 16
(E) 19
Answer:
Work done by P in 1 day = 1/24
Work done by Q in 1 day = 1/9
Work done by R in 1 day = 1/12
Work done by Q and R in 1 day = 1/9 + 1/12 = 7/36
Work done by Q and R in 3 days = 37/36 = 7/12
Remaining work = 1 7/12 = 5/12
Number of days in which P can finish the remaining work = (5/12) / (1/24) = 10
The answer is (B).