If simple interest on Rs. 600 for 4 years and on Rs. 600 for 2 years, combined together is Rs. 180, find the rate of interest?

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

$1, 4, 18, 44, 83, ?$

Which of them is wrong in the following number series?

$3, 4, 9, 33,136, 685, 4116$

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

7, 48, 87, ?, 159

What should come next in the following number series?

$9,1,8,2,7,3,6,4,5,9,1,8,2,7,3,6,5,9,1,8,2,7,3,5,9,1,8,2,7$

Find the missing number of the given series:

$46080, 3840, 384, 48, 8, 2, ?$

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

$1328, 1722, 2188, 2732, 3360, ?$