In this question, the weight is going with a pattern of
2 ; 4; 6; 8; 10
0.8 ; 1.4; 2.0; 2.6; 3.2
If you look at it closely, it is clear that the difference for each of them is 2 weeks and 0.6 pounds.
Because the question is asking for initial value, then you need to subtract the first number with the pattern. it would be: 0.8 pound- 0.6 pound= 0.2 pound