Sorry, I can't answer that as it would ruin the fun for others yet to play! :nono: :smiley7:

I think it would be 8 + 11, plus the 21 above the missing number in the 3rd column = 40, not 96. What am I missing here?

99

8 x 11 + 11 = 99

Okay

176





.

Here is how I got 96.
Obviously 1+4=5, but 2+5 does not =12, and 3+6 does not equal 21. So there is a hidden function going on.
I used the first number as a multiplier of the second number, then added the first number to that to get the answer.
1+(4 x 1)=5
2+(5 x 2)=12
3+(6 x 3)=21
8+(11 x 8)=96

Interestingly, if you do this equation starting at 0+3 and carry it on in the same progression from there, you will get a progression of uneven positive numbers in steps of two as the difference of the answers. I know, that is confusing. Let me show the work.

0+(3 x 0)=0
1+(4 x 1)=5 a difference of 5 from the answer before.
2+(5 x 2)=12 a difference of 7 from the answer before.
3+(6 x 3)=21 a difference of 9 from the answer before.
4+(7 x 4)=32 a difference of 11 from the answer before.
5+(8 x 5)=45 a difference of 13 from the answer before.
6+(9 x 6)=60 a difference of 15 from the answer before.
7+(10 x 7)=77 a difference of 17 from the answer before.
8+(11 x8)=96 a difference of 19 from the answer before. (Again interestingly, 19 is the answer to a normal 8+11 equation.)
and continue on in this pattern indefinitely.
NOTE: this is not a ground breaking revelation in mathematics, :rotf:! It's just something I found interesting.

Two possible ( at least) solutions to this one.
(x+a)*(y+b)=n
Solving gives us two possible choices for a and b
(x+0)*(y+1)=n :a=0,b=1 or
(x+4)*(y-3)=n :a=4, b=-3
(1)*(4+1)=5
(2)*(5+1)=12
(3)*(6+1)=21
(8)*(11+1)=96
or
(1+4)*(4-3)=5
(2+4)*(5-3)=12
(3+4)*(6-3)=21
(8+4)*(11-3)=96
So 96 would seem to be the answer with at least 2 ways to get there.
C.G.B.

So I gave this problem to a female with a degree in mathematics (wife) and you get a whole new perspective. "You only have what is presented. You are not looking for some general solution. You only have to deal with what is on the paper. The answer is 40!"
I say 'Splain it Lucy" and here is what I get (with some sarcasm):
1+4=5
2+5=1+2+4+5=12
3+6=1+2+3+4+5+6=21
8+11=1+2+3+8+4+5+6+11=40
How can you argue with that?
C.G.B.

Seems like we're making this more difficult than it really is. I'd think the answer would come in the matter of seconds without an equation formula? Just my take on it....when do we get the answer? I think I came up with 40 under 20 seconds. My formula is on the 2ND page. I'm curious if I'm right or wrong???

it is 40