Hi there!
You would add for this problem.
If you're wondering why, the answer is very simple. You just have to look for key words. I saw the word "grow".
If grow means to increase, and so does "add", then you will need to add.
Hope this helps! :)
X*.50= the longer chain
X is how long the first chain is.
It is correct, because they wanted 50% more. More meaning multiply so you would multiply x the first chain times how mor long it needs to be.
L= 1/8
O=1/4
C=1/8
H=1/8
S=1/8
O or L=3/8
S or C=1/4
S or C or O=1/2
OR mean to add.