A dodder plant wraps itself around a potato plant. The dodder then uses its root system to obtain water and nutrients from the potato plant. Which statement best describes this scenario?

The potato plant is parasitic.
The dodder plant is a host.
The potato plant stays alive because of the dodder.
The dodder plant stays alive because of the potato plant.

Rick gave his son $100 to buy food and drinks. His son returned with $25.50 in change. Therefore the amount spent was
$100 - $25.50 = $74.50.

Let
x = number of hot dogs bought (at $3.50 per hot dog).
y = number of milk shakes bought (at $8 per milk shake).
There were 8 orders of soda at $5 per soda.

The total order is $74.50, therefore
3.50x + 8y + 8*5 = 74.50
Simplify to obtain
8y = 74.5 - 3.5x
  y = 4.3125 - 0.4375x

We must have whole numbers (integers) for x and y.
Create a table that varies x from 0 to 8, and look for y to be an integer, as shown below.

  x       y
---  
 0   4.3125
 1    3.8750
 2   3.4375
 3   3
 4   2.5625
 5   2.1250
 6   1.6875
 7    1.2500
 8    0.8125

Because we cannot have fractional values for either x or y, the solution is x=3, y=3

3 hot dogs, 3 milk shakes, and 8 sodas.