Answer: 
Step-by-step explanation:
Given : A man earned x pesos in 10 days and spent y pesos during each of those days.
i.e. Total earning in 10 days = x
Earning per day =
[By unitary method] (1)
Money spent per day =y (2)
We know that

i.e. Subtract (2) from (1), we get

Hence, the expression to determine how many pesos he saved per day will be:-

100 barrels * 50 liters = 5000 liters of water. 1 kiloliter = 1000 liters, so there are 5 kilo liters
For this case we have the following variables:
x: the number of minutes of television Sam watched each day
y: the number of minutes she spent exercising
Then, we have the following function that models the problem:

if she spends 30 minutes watching television we have x = 30.
Substituting in the given equation we have:

Answer:
the best prediction for the number of minutes of exercising Sam will do if she spends 30 minutes watching television that day is:
72 minutes
School sells lunch for $5.50 dollars per day for 5.3 days, if sally has $25.60 than will she be able to buys lunch for those 5.5 days
1- Multiply 5.5 times 5.3 (number of days)
2-Take 25 and divide it by that number