Step 1: Translate Given Information into Algebra Expression
For this question, we are looking to write an expression to represent a certain total. The starting amount will be an unknown amount and every other amount will be written in terms of the initial amount.

In the given prompt, we know that Orlando drove an unknown number of miles during his first week, so the number of miles he drove that week will be assigned a variable x.

Number of miles driven first week → x

We are also given that Orlando drove fifteen more miles in his second week in comparison to the number he drove in the first week. This means,

Number of miles driven in the second week → x+15

Finally, we are told that he drove twenty-five fewer miles in his third week when compared to the first week. Since he drove fewer miles, this means we will be subtracting 25 miles from the amount he drove the first week which is represented by x.

Number of miles driven in third week → x–25

Step 2: Determine Total
Now that we have all the individual expressions, we can find the final sum.
We are asked to write an expression that represents the total number of miles that Orlando drove in the 3-week road trip. To find the total, we need to find the expression that adds all the expressions and simplify.

x+x+15+x–25

We can now rearrange the expression to group like terms together. Remember to include the sign IN FRONT of a term.

x+x+15+x−25

Now becomes:

x+x+x+15−25

The expression becomes:

3x–10

Step 1: Interpret the Prompt
In this type of scenario, you are given the items and the price of each one. The first step is to define the variables that will represent the number for each item.

s = number of shirts bought
p = number of pants bought

The cost of a shirt is $6.50, therefore, the expression that represents the total Thomas will spend on the shirts = 6.50s

The cost of pants is $12, therefore, the expression that represents the total Thomas will spend on pants = 12p

Step 2: Write Your Inequality
In this case, we are told he has $64, which means he can spend at most $64. This means he can spend less than or equal to $64 so we know the symbol “<” will be involved.

Knowing that the total he will spend is the sum of what he spends on shirts (6.50s) and the total he will spend on pants (12p), now we can construct our inequality:

6.50s+12p < 64