For the unit rate, you are looking for how much one unit of something costs. Looking at the table, you'll see that 3 bottles of fragrance A costs $78. What you want to figure out is how much one bottle costs.
You can do this by taking the price and dividing it by how many there are.
78 ÷ 3 = $26
156 ÷ 6 = $26
234 ÷ 9 = $26
You can see that each bottle of fragrance A costs $26.
Now looking at the graph, you'll see that the line only lines up perfectly at 2 points: (1, 24) and (2, 48). This tells us that for each bottle of fragrance B, it costs $24.
Comparing the two, fragrance A will have the greatest unit rate.
The total amount Serena earns is the sum of her regular wage and the tips. The amount she earns from the wage is equal to 9h. This total should be more than or equal to $110. This is mathematically expressed as, 9h + 15 ≥ 110
