In a geometric progression consisting of positive terms, each term equals the sum of the next two terms. Then the common ratio of this progression equals

• 
• 
• 
• 

D.

 then the value of x

• 1

• 3

• 4

• 5

B.

3

In the binomial expansion of (a - b)n, n ≥ 5, the sum of 5th and 6th terms is zero, then
a/b equals

• 5/n −4

• 6 /n −5

• n -5 /6

• n -4 /5

D.

n -4 /5

The set S: {1, 2, 3, …, 12} is to be partitioned into three sets A, B, C of equal size. Thus, A ∪ B ∪ C = S, A ∩ B = B ∩ C = A ∩ C = φ. The number of ways to partition S is-

• 12!/3!(4!)³

• 12!/3!(3!)⁴

• 12!/(4!)³

• 12!/(3!)⁴

A body weighing 13 kg is suspended by two strings 5 m and 12 m long, their other ends being fastened to the extremities of a rod 13 m long. If the rod be so held that the body hangs immediately below the middle point. The tensions in the strings are 

• 12 kg and 13 kg

• 5 kg and 5 kg

• 5 kg and 12 kg

• 5 kg and 13 kg

C.

5 kg and 12 kg