First question :

1+1=101

2+3=32

3+4=304

4+12=?

Answer : 124

I took the second number as two digit number.

1+01=1 01 (not swap)

2+03=03 2 (swap) but in above question i ignored zero

3+04=3 04 (not swap)

4+12=12 4 (swap)

Second question :

1+1=11

2+2=44

3+3=99

4+4=?

Answer : 1616

1^2+1^2=11 (1^2 =1 to the power of 2 or 1 square)

2^2+2^2=44 (2^2 =1 to the power of 2 or 1 square)

3^2+3^2=99 (3^2 =1 to the power of 2 or 1 square)

4^2+4^2=1616 (2^2 =1 to the power of 2 or 1 square)

Third question :

1+1=11

2+2=24

3+3=39

4+4=?

Answer : 416

1+1^2=11

2+2^2=24

3+3^2=39

4+4^2=416

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