Series Riddles

5
(8+7)*5=75

125

cube of prime numbers
2*2*2
3*3*3 and so ...

89

13 -21 34 -55 ? -144
The number is differnce between right number and left number.
i.e

example
13-(-21) = 34
-21-(34) = -55
34-(-55) = 89 answer
-55-(89) = -144

Both 0 and 16 will suffice the missing number.

This is because, there is no specific pattern in this picture. The only thing that you will notice is that the numbers are continuous and jumbled up.
Thus the number can be 0 or 16.

29

The center number is the product of the largest cornering numbers minus the square of the smallest one.

Thus the number is:
45 – 16 = 29

He's your grandson.

This is because:
Uncle's sister would either be your mother or your aunt. But since you have asked for the closet relation, it would be your mother.
Your mother's granddaughter would be either your daughter or your niece. But daughter is the closest.
Further, your daughter's son is without a fail your grandson.

13/9
3 5/3 7/5 11/7 13/9 17/11

Numerator is prime number series 3,5,7,11 13 17
and Denominator is +2 series 1(1=1/1),3,5,7,9,11

48

2 + 2= 4 (2*2*1)
3 + 3= 18 (3*3*2)
4 + 4= 48 (4*4*3)
6 + 6= 180 (6*6*5)

The last missing throw will have 3 as the result. This is because, with each pair of the throws you can find that the total sum is increasing by three and then decreasing by one. Therefore the missing throw be 3.

The missing number is 60.

1 + 5 = 12
=> 1*2 + 5*2 = 12

2 + 10 = 24
=> 2*2 + 10*2 = 24

3 + 15 = 36
=> 3*2 + 15*2 = 36

Similarly,
5 + 25
=> 5*2 + 25*2 = 60