Final answer:
Natalie's group can purchase 16 sodas with $20 from the concession stand, as each soda costs $1.25 and $20 divided by $1.25 equals E)16.
Step-by-step explanation:
The question asked is: How many sodas can Natalie's group buy with $20 if a medium soda costs $1.25? To answer this, divide the total amount of money Natalie has ($20) by the cost of one medium soda ($1.25). This calculation is performed as follows:
$20 ÷ $1.25 = 16 sodas
This means that Natalie's group can buy 16 sodas with $20. Therefore, the correct answer is E) 16 sodas.