26. If a - b = 3 and a^2 + b^2 = 29, find the value of ab.

Ans :10

Explanation:
2ab = (a² + b²) - (a - b)²
   = 29 - 9 = 20
   ab = 10.

25. In how many ways can a group of 5 men and 2 women be made out of a total of 7 men and 3 women?

Answer: 63

Explanation:

Required number of ways = (7C5 x 3C2) = (7C2 x 3C1) =		7 x 6	x 3		= 63.
		2 x 1

24. Find the output.

void main()
{
int i=3, *j, k;
j = &i;
printf("%d\n", i**j*i+*j);
}

Answer: 
30

23. A triangle is made from a rope. The sides of the triangle are 25 cm, 11 cm and 31 cm. What will be the area of the square made from the same rope?

Solution: 

Add all sides 25+11+31 to get rope length rope length =67,rope is made in to as square. So side of square is 67/4=16.75 and so area is 16.75*16.75=280.5625.
Ans : 280.5625

22. If DDMUQZM is coded as CENTRAL then RBDJK can be coded as _____

Ans : QCEIL

21. Four different integers are in increasing AP such that one number is equal to sum of the squares of the other three numbers.

Ans : 1,0,1,2

20. Rs 1,050 are divided among P, Q and R. The share of P is 2/5 of the combined share of Q and R. P gets ?

Ans : Rs 300