x + 15 = 24
subtract 15 from both sides
x = 24 - 15 = 9
we know that
1 gal.= 3.8L
we can also write as
3.8L=1 gal
Firstly, we will find for 1L
so, we can divide both sides by 3.8


now, we will multiply both sides by 22



so, option-b.............Answer
I think it would be easy to find it because its 30 feet away and even if he didn't know his feet he could always leave rocks/pebbles to the treasure so he won't lose it.
3/10 * 2/9 = 1/15
There is a 1/15 chance that both of the shirts he grabbed are black....
:)