What will come in place of the question mark (?) in the following number series?

3240, 540, 108, 27, ?, 4.5

Which number will fit in '?' place in the following series?

12, 23, 45, 89, ?

Assuming that the numbers in each of the following figures follow a similar pattern, select the option that can replace the question mark (?) in figure C.

The equation of a line is given by 4y-6x+9=0. Find the slope of other line which is perpendicular to it.

What will be the 20th term in the given sequence?

-50, -47, -44, _

In the given series of numbers how many 7's are there which are immediately followed by 9 and immediately not preceeded by 5 ?

The value of 1+22+23+24+...+29 is

In an arithmetic progression if 13 is the 3rd term, -­47 is the 13th term, then ­-17 is which term?

What is the value of (81 + 82 + 83 + ......... +130)?