How to calculate the amount of sales tax?

1.      Convert tax percentage into a decimal by moving the decimal point two spaces to the left.
2.      Multiple the pre-tax value by the newly calculated decimal value in order to find the cost of the sales tax.
3.      Add the sales tax value to the pre-tax value to calculate the total cost.

Calculating sales tax at time of purchase:

In order to calculate the sales tax of an item, we need to first multiply the pre-tax cost of the item by the sales tax percentage after it has been converted into a decimal. Once the sales tax has been calculated it needs to be added to the pre-tax value in order to find the total cost of the item. Let's start by working with an example. If a magazine costs $2.35 and has a 6% sales tax, then what is the total cost of the item. First, we need to convert the sales tax percentage into a decimal by moving the point two spaces to the left.

Now, we need to multiply the pre-tax cost of this item by this value in order to calculate the sales tax cost.

Round to two decimal places since our total is in dollars and cents.

Last, add this value to the pre-tax value of the item to find the total cost.

Calculating the sales tax percentage of a total:

If we are given the total cost of an item or group of items and the pre-tax cost of the good(s), then we can calculate the sales tax percentage of the total cost. First, we need to subtract the pre-tax value from the total cost of the purchase. Next, we need to create a ratio of the sales tax to the pre-tax cost off the items. Last, we need to create a proportion where the pre-tax cost is related to 100% and solve for the percentage of the sales tax. Let's start by working through an example. If a person pays $245.64 for groceries that cost $220.00 pre tax, then what is the sales tax percentage for the items.

First, subtract the pre-tax value from the total cost of the items to find the sales tax cost.

Next, create a ratio of the sales tax to the pre-tax cost of the items.

Last, create a proportion where the pre-tax value is proportional to 100% and solve for the percentage of sales tax.

Cross multiply and solve.

Isolate the sales tax percentage to the left side of the equation by dividing each side by the pre-tax value.

Round to two decimal places since our answer is in dollars and cents.

Last, we can check this answer by calculating the sales tax percentage of the total as seen previously.

First, we need to convert the sales tax percentage into a decimal by moving the point two spaces to the left.

Now, we need to multiply the pre-tax cost of this item by this value in order to calculate the sales tax cost.

Round to two decimal places since our total is in dollars and cents.

Last, add this value to the pre-tax value of the item to find the total cost.

Our answers check out; therefore they are correct. Now, let's use this information to solve the given problem.

Solution: 

Multiply the sales percentage with the cost of the bike before sales tax.  This will determine the amount of tax the buyer must pay.

A percent is a number out of 100 parts. 

Multiply the price with the percent.

The tax on the bike is:  

How to calculate the amount of sales tax?

1.      Convert tax percentage into a decimal by moving the decimal point two spaces to the left.
2.      Multiple the pre-tax value by the newly calculated decimal value in order to find the cost of the sales tax.
3.      Add the sales tax value to the pre-tax value to calculate the total cost.

Calculating sales tax at time of purchase:

In order to calculate the sales tax of an item, we need to first multiply the pre-tax cost of the item by the sales tax percentage after it has been converted into a decimal. Once the sales tax has been calculated it needs to be added to the pre-tax value in order to find the total cost of the item. Let's start by working with an example. If a magazine costs $2.35 and has a 6% sales tax, then what is the total cost of the item. First, we need to convert the sales tax percentage into a decimal by moving the point two spaces to the left.

Now, we need to multiply the pre-tax cost of this item by this value in order to calculate the sales tax cost.

Round to two decimal places since our total is in dollars and cents.

Last, add this value to the pre-tax value of the item to find the total cost.

Calculating the sales tax percentage of a total:

If we are given the total cost of an item or group of items and the pre-tax cost of the good(s), then we can calculate the sales tax percentage of the total cost. First, we need to subtract the pre-tax value from the total cost of the purchase. Next, we need to create a ratio of the sales tax to the pre-tax cost off the items. Last, we need to create a proportion where the pre-tax cost is related to 100% and solve for the percentage of the sales tax. Let's start by working through an example. If a person pays $245.64 for groceries that cost $220.00 pre tax, then what is the sales tax percentage for the items.

First, subtract the pre-tax value from the total cost of the items to find the sales tax cost.

Next, create a ratio of the sales tax to the pre-tax cost of the items.

Last, create a proportion where the pre-tax value is proportional to 100% and solve for the percentage of sales tax.

Cross multiply and solve.

Isolate the sales tax percentage to the left side of the equation by dividing each side by the pre-tax value.

Round to two decimal places since our answer is in dollars and cents.

Last, we can check this answer by calculating the sales tax percentage of the total as seen previously.

First, we need to convert the sales tax percentage into a decimal by moving the point two spaces to the left.

Now, we need to multiply the pre-tax cost of this item by this value in order to calculate the sales tax cost.

Round to two decimal places since our total is in dollars and cents.

Last, add this value to the pre-tax value of the item to find the total cost.

Our answers check out; therefore they are correct. Now, let's use this information to solve the given problem.

Solution: 

Find the tax () by multiplying the retail price by the total sales tax rate.

Start by converting the state and city sales tax percentages into decimals:

Then set up the equation as follows:

The account begins at $175 and then earns 15% interest:

If the account owner takes out 76% of the available balance, that means that 24% off the account will be remaining:

$48.30 remains

John started out with $8,000 and increased it by 12% after a year. This indicates that by the end of the year, he has 112% of $8,000 (The original $8,000 plus the 12% return from his investments). Convert 112% into its decimal equivalent of 1.12 and multiply it by $8,000 to get John's current savings amount:

The formula for simple interest is

where  is the amount that's loaned to you,  is the annual interest rate, and  is the time (in years) interest accumulates. In this problem,

and

Plug these values in:

So in three years, you will owe an interest of $192.

To solve this, multiply 12,000 by the decimal equivalent of 5% (.05). This gives a total interest of $600.

The formula in calculating interest is

,

where  is the principal,  is the annual interest rate in decimal form, and  is number of years the principal accrues interest.  In this problem, , , and .

To find the interest, plug these values into the equation:

Therefore the accrued interest is $525.

When finding simple interest, we use the following formula:

The principal (P) equals the amount we deposit or invest.  In this case,

The rate (R) is the percentage rate at which the principal increases or decreases.  In this case,

because we must convert 5% into decimal form. 

The time (T) equals the number of years the money is accruing interest.  In the case,

So, according to the formula above

Therefore, the total interest earned is $375.

To calculate the amount of interest she earned, we use the formula:

, where  is the principal (the initial amount invested)  is the interest rate, and  is the amount of time, in years, passed.

Plug the given values into the above formula:

Remember, when calculating interest, percents needed to be converted to decimals.

To calculate the percent interest of Sal's account, we arrange the simple interest formula:

Solve for the interest rate,

Plug in the appropriate values

Simplify.