Answer:
D = 30/7; R =32/7
Explanation:
First, we need to find the scale of the number line. We can see that there are 7 ticks between 4 and 5. Thus, we can use (5-4)/7 to find the scale which is 1/7.
Since D is two ticks away from 4, we can use the equation:
Since R is two ticks away from D or 30/7, we can use a similar equation:
Your problem doesn't tell us whether we need to we use improper or mixed fractions, but I've included both for you.