To find the amount of miles/gallon, we have 540 miles/18 gallons=30 miles/gallon. As we add 30 miles for every gallon, the amount of miles traveled is 30*x (e.g. if x is 1 then 0+30=30 and if x is 2 then 30+30 (2 times)=60) with x being the amount of gallons. For b, we just plug 12 in for x to get 20*12=360
As in each table can seat 8 people and the probability you need to find is about the first person you can ignore this data.
Probability that the first person to enter the room will be randomly seated at a maple table:

#maple tables: 9
# total tables: 9 +10 +5 +7=31

Then, the probability that the first person to enter the room will be randomly seated at a maple table is 9/31
She needs 15 crates of limes
2x6=12
40x6=240 limes required to make 12 liters
240/16=15 crates needed
That was made up?cz I tried to solve it and I kept getting different #s
X=-13/5
Simplify both sides of the equation, isolate the variable, and then you get your answer.