CBSE - Aptitude Mathematics

The operation * applied to a number gives as its result 10 subtracted from twice the number. What is *(*9)? 1. -11 2. 6 3. 8 4. 9

The length, breadth and height of a room are 5 meter, 4 meter and 3 meter respectively. Find the area of the four walls. 1. 54 sq.m 2. 60 sq.m 3. 34 sq.m 4. 36 sq.m

Find x when x + y = 4, and 2y = 6. 1. 1 2. -2 3. -3 4. -1

Two numbers are in the ratio of 2 to 3, and if 9 be added to each, they are in the ratio of 3 to 4. The numbers are 1. 6 and 9 2. 18 and 27 3. 12 and 18 4. 8 and 12

Murali, Murari and Muthuswamy can erect a wall in 10 days. After working at it together for 4 days, Murali leaves with other's consent, an then Murari and Muthuswamy finish it in 10 days. In how much time can Murali alone erect the wall? 1. 28 days 2. 25 days 3. 30 days 4. 24 days