# Basic Arithmetic : Linear Equations with Money

## Example Questions

### Example Question #1 : Linear Equations With Money

If Bobby makes  an hour plus a  bonus a day, how much would Bobby make if he works  hours today?

Explanation:

1. Find the equation from this scenario:

Since Bobby makes $12 an hour, you know that your slope is 12 because his total pay will be the$12 multiplied by the number of hours he worked.

Add the $5 daily bonus Bobby makes, which is your y-intercept in this equation. Total =$12(hours) + $5 2. Find his total pay for 5 hours using the above equation:$65

### Example Question #1 : Linear Equations With Money

Tom makes  a day,  days a week.  If his rent every four weeks was , what is his overall net profit?

Explanation:

We can determine Tom's weekly income by multiplying $50 into the 5 days he worked. Tom makes$250 a week.

In four weeks, Tom makes $1000. Since his rent was$1000 every four weeks, his net income is zero.

### Example Question #1 : Linear Equations With Money

You loan a friend  at a  annual simple interest rate. After how many years will he owe you  just in interest?

year

years

years

years

years

year

Explanation:

This is a simple interest rate problem, for which we use the formula:

Interest = P x r x t

P is the principal, or original loan amount; r is the annual interest rate; and t is the number of years in question.

In this problem we are given the interest ($100); the principal ($2,000); the interest rate (5%). We are asked to find t, the time in years it takes for $100 of interest to accumulate. We plug all these values into the formula and solve for t: t is equal to 1 year. It will take 1 year for$100 of interest to accumulate.

### Example Question #1 : Linear Equations With Money

A lollipop costs .  Anne has  dollars.  What is the maximum number of lollipops Anne can buy? How much money does she have left over (round to the nearest whole cent)?

lollipops with  left over.

lollipops with  left over.

lollipops with  left over.

lollipops with  left over.

lollipops with  left over.

lollipops with  left over.

Explanation:

To solve this problem, first you need to create a linear equation:

Divide both sides by :

.

.

Now, Anne can't buy .462 lollipops, so you round off to  Now you must calculate the money left over:

.

So, Anne bought  lollipops and she has  left over.

### Example Question #1 : Linear Equations With Money

Jim makes  per hour.  If he works  hours per day for  days, how much money will he earn?

Explanation:

Since Jim makes 12 dollars per hour we can multiply 12 by the number of hours he worked. We then can multiply that number by the number of days he worked to get the total money earned.

Convert back into dollars, so you have .

### Example Question #21 : Money And Time

Mark has taken his car down to his local car wash. There, he can wash his car for  per minute, and dry his car at the end of the wash for a flat  fee. If Mark only has  to spend on a car wash, for how long can he wash his car?

minutes.

minutes

minutes

minutes

minutes

minutes.

Explanation:

To figure out how many minutes Mark can wash his car, we must understand the relationship between the total cost of a car wash and the length of the car wash.

With every car wash, a fee of  is needed to dry the vehicle, so Mark will only have  remaining to spend on washing his car. If it costs  per minute to wash his car, we merely need to divide  by  to determine the number of minutes that Mark can wash his car:

Therefore, with Mark's , he can wash his car for  minutes.

### Example Question #1 : Linear Equations With Money

Jamie makes $60 a day, 5 days a week. If her rent is$300 every 4 weeks, what is her net profit in 4 weeks?

Explanation:

In 4 weeks, Jamie will automatically be spending $300 on rent, so we will subtract this amount from whatever income Jamie makes. In order to calculate her income, we will multiply$60 by 5, which equals $300. Jamie makes$300 a week.

Then we will multiply this number by 4, since we are finding her net profit over 4 weeks. $300 times 4 equals$1200.

Lastly, we subtract her rent payment ($300) from her$1200 income, making her net profit $900. ### Example Question #1 : Linear Equations With Money Samuel bakes cakes and earns$5 profit from each cake. This week, he made 25 cakes. One cake was so beautiful, that the customer tipped Samuel an extra $25. How much money did Samuel earn this week? Possible Answers: Correct answer: Explanation: To calculate how much money Samuel made this week, we will multiply how many cakes he made with how much profit he earns per cake. This week, Samuel made 25 cakes at$5 profit per cake, so we will multiply 25 by $5, which equals$125.

On top of this, we will add the $25 tip given to Samuel, which comes to a grand total of$150 earned this week.

### Example Question #1 : Linear Equations With Money

It costs $8 to enter the carnival, and then each ride costs$2 to ride. Landry only has time to ride 4 rides. How much money does he spend at the carnival?

Landry rides 4 rides at the carnival, which cost $2 each. To determine their total cost, we will multiply 4 by$2, which equals $8. Then we need to add the initial cost of entering the carnival, which is also$8. Adding these together, we find that Landry spent $16 at the carnival. ### Example Question #1 : Linear Equations With Money Bill receives a monthly stipend of$500. He also works a part-time job, earning $30 a day. This month, he worked 10 days. How much money did he receive this month? Possible Answers: Correct answer: Explanation: First, we want to determine Bill's income this month, independent of his stipend. We calculate his income by multiplying$30 by how many days he worked in a month. In this case, he worked 10 days. Therefore, we multiply $30 by 10, which equals$300.
Since Bill also has a consistent monthly stipend of $500, we add his income of$300 to his stipend of $500, which totals$800.