4. 10.
1,2,4 1,2,5,10
2 is the greatest common factor.
Kayla will receive $1.81 change.
10.00-8.19= $1.81
X = 2
X+3=5
Subtract 3 from 3 and 5
The equation remaining is x = 2
Answer:

Step-by-step explanation:
x - number of adults
y - number of campers
<em>The room for 200 people</em>: x + y ≤ 200
<em>Each adult costs $4, and each camper costs $3</em>: 4x and 3y
<em>A maximum budget of $750</em>: 4x + 3y ≤ 750