MindTree aptitude placement paper

First time I heard about MindTree was only when it came to our college for campus placements. They chose 5 out of 70 candidates who attended the placement test. A friend of mine made it through and tells me that its a good company over all. Some of the quantitative aptitude questions they asked are:

(1/3) of a number is 6 more than the (1/6) of the same number?
a) 6 b)18 c)36 d)24

If a tank A can be filled within 10 hours and tank B can be filled ¼ in 19 hours. How long will it take for both the pipes together to fill up the tank completely?
a) 21 B) 38 c) 57 d) 76

In the reading room of a library, there are 10 tables, 4 chairs per table. In each table there are different numbers of people seated. In how many ways can they can sit in the library so that no chair is left blank?
a) 8 b) 6 c) 2 d) 7

4, 7, 10, 11, 22, 17, 46, 25, ‘?’
a.) 58 b.) 69 c.) 86 d.) 94 e.) 81

Which of the following is a perfect square?
a.) 19210 b.) 23435 c.) 28561 d.) 17466

Amitabh forms rows and columns of 18496 pebbles on floor such that there are as many rows as there are pebbles in each row. The number of rows is
a) 126 b) 146 c) 136 d) 156


At what rate percent per annum will a sum of money double in 10 years?
a) 10% b) 11% c) 12% d) 13%