Question

1+4=5 2+5=12 3+6=21 8+11=?

Answer 1

Solution :-

1+4 = 5 : 2+5 = 12 ; 3+6 = 21 ; 8+11 = ?

If we see the series then we will find the numbers in the series in this way.
# (1*4) + 1 = 5
   4+1 = 5

# (2*5) +2 = 12
   10 + 2 = 12

# (3*6) + 3 = 21
  18 + 3 = 21

# (4*7) + 4 = 32 [Which is not given in the series]
   28 + 4 = 32

# (5*8) + 5 = 45 [Which is not given in the series]
   40 + 5 = 45

# (6*9) + 6 = 60 [Which is not given in the series]
   54 + 6 = 60

# (7*10) + 7 = 77 [Which is also not given in the series]
   70 + 7 = 77

# (8*11) + 8 = 96 [Number about which is the question is asked]
   88 + 8 = 96

So, the missing number in the series will be 96.

Answer 2

This question is trivial in nature since it did not follow the logic for mathematics.

To answer this riddle, we would follow the equation: a + ab

1 + 4 means 1 + 1(4) = 5
2 + 5 means 2 + 2(5) = 12
3 + 6 means 3 + 3(6) = 21

Therefore, the answer to 8 + 11 is

8 + 8(11) = 96

I hope I was able to help.