Which one set of letters when sequentially placed at the gaps in the given letter series shall complete It?
_c_bd_ cbcda_a_db_a

Find the odd letters from the given alternatives.

DIRECTIONS: Arrange the following in the meaningful/logical order:
1. Exhaust
2. Night
3. Day
4. Sleep
5. Work

If x – y + z = 15, xyz = -216 and xz – xy – yz = 18, then the value of $$ {x^3}-{y^3}+{z^3}=$$

If 0.4 m + 0.8 n = 2.2 and 0.8 m + 0.4 n = 1.4, then the value of $$ {m^2}+{n^2}$$ is equal to 

If $$ {x^2} -4x-1 $$ then the value of $$ {{x^6} -{x^4}+{x^2}-1}\over {x^3}$$ will be

The difference between the interior and the exterior angles of a regular polygon is 150^o. Find the number of sides in the polygon.

If the amount is $$ 3{3\over8}\%  $$ times the sum after 3 years at compound interest compounded annually, then the rate of interest per annum is