Final answer:
Parker will need 2 1/2 cups of dip.
Step-by-step explanation:
To find out how many cups of dip Parker will need, we can set up a proportion using the given information. 
The snack mix recipe calls for 1 1/4 cups of dip and 1/2 cups of veggies. 
Let's call the number of cups of dip Parker needs x. 
The proportion will be: 1 1/4 cups / 1/2 cups = x cups / 1 cup. 
To solve for x, we can cross multiply and then divide: (1 1/4) * 1 = (1/2) * x. 
Simplifying both sides gives us 5/4 = 1/2 * x. 
To isolate x, we can multiply both sides by the reciprocal of 1/2, which is 2/1: (5/4) * (2/1) = x. 
Multiplying gives us x = 10/4, which simplifies to x = 2 1/2 cups.