Heather will be 6 and 7 months old
This equation has no solution where 'a' and 'b'
are both non-zero real numbers.
You said 2a + 2b = 2a
Subtract 2a from each side: 2b = 0
'b' must be zero.
And it doesn't matter what the value of 'a' is.
As long as b=0, 'a' can be any number.
Problem A,B,C, and D can be solved using 3*6=18 or 6*3=18