The answer is no relationship (edit)
In total, there are 40 marbles. 25 of those marbles are green. What I did was divide the number of green marbles by fourth, the total number of marbles. (25/40) You should come up with 0.625. Then you convert the decimal into a fraction. 5/8 is equivalent to 0.625. Thus, 5/8 of the marbles are green.
Hope this helps :)
The answer is b
If you go backwards on a number line, you are subtracting--which is the same as adding a negative.
First you go backwards 3 numbers, and then to get to -7, you went down (decreased) by 4 more, or subtracted 4 (added a negative 4)