You can set up proportions 4 different ways, but the answer is going to be the same regardless.
I am going to create to ratios comparing the number of apples to the price you pay
Six apples/ $1 Is one of the ratios
15 apples/ $d This is the other ratio
Now, make them equal to each other
6 apples/ $1 = 15 apples/ d
d= $2.50 Divide both sides by 6.
This should be our answer. 15 apples for 2.50
D. Y. Taylor