I'm learning about specific gravity and I need a little help.

Say you have 5 bottles of sal****er solution. You know the percent of
salt each bottle contains and it's specific gravity. For example:

5% = 1.050
10% = 1.080
15% = 1.120
20% = 1.150
25% = 1.200

Now what if you had a bottle that contained an x% of salt but it's
specific gravity was 1.100. How would you calculate how much percent
of salt the bottle contains?