I am Maya. Welcome back! Have you ever had exactly ten dollars in your hand, found a toy for nine dollars and ninety-nine cents, but then the cashier told you it wasn’t enough? It’s a frustrating moment, right? That is because of sales tax! In most of Canada, the price you see on the shelf is not the final price you pay. Today, we are learning the math of “The Real Total.” We’re going to master estimating and calculating prices with tax so you are always prepared at the register!I am Liam. I’ll admit, tax used to confuse me. But I’ve learned a secret: you can estimate tax in your head in just a few seconds! It’s a mental math strategy that makes you look like a shopping expert. I’ll show you how to use your “ten-percent brain” to never be surprised by a total again. No more scratching your head at the checkout counter for us!I am Chloe. I love the details! I’ll be showing you the exact math. We are going to work with dollars and cents using decimals to the hundredths place. Whether it is a thirteen percent tax in Ontario or a five percent tax elsewhere, we’re going to use our multiplication and addition skills to find the perfect answer. Precision is key when you’re managing your savings!And I am Noah. I have a special rule to share: the Cash Rounding Rule. Since we don’t use pennies in Canada anymore, we have to know how to round our totals to the nearest five cents. It’s a simple rule, but if you don’t know it, your change might not be what you expect. Let’s head to the Game Store and start shopping!Imagine you want to buy a new game controller for thirty dollars. That sounds like a nice, round number. But wait! We live in Ontario, where the Harmonized Sales Tax, or HST, is thirteen percent. To estimate the total, let’s use the “10 plus 3” method. First, find ten percent. That’s easy—you just move the decimal point one place to the left. Ten percent of thirty dollars is three dollars. Now, we need to find that extra three percent. If ten percent is three dollars, then one percent is thirty cents. Three times thirty cents is ninety cents! Add them together: three dollars plus ninety cents equals three dollars and ninety cents in tax. Our estimated total is $30 + $3.90 = \$33.90$. If you have a fifty-dollar bill, you can instantly see that you’ll get about sixteen dollars back. This is a pro strategy because it helps you decide if you have enough money before you stand in line!Now, let’s look at the exact calculation for your records. In math class, we represent thirteen percent as the decimal zero point one three. To find the tax, we multiply:
$$30 \times 0.13 = 3.90$$
. Then, we add that tax back to the original price:
$$30.00 + 3.90 = 33.90$$
. Now, let’s calculate the change from that fifty-dollar bill. We take our fifty dollars and subtract our total:
$$50.00 – 33.90 = 16.10$$
. See how close our estimate was? Practice with these decimals helps you understand place value, which is a huge part of Grade 5 math. Remember, we always use a dollar sign and two decimal places for cents. It’s the professional way to write currency!But wait, there is one more step if you are paying with physical cash! In Canada, we retired the penny in 2013. That means if you pay with coins and bills, the total has to be rounded to the nearest nickel, or five cents. Here is the rule: If the total ends in a one or a two, we round down to zero. If it ends in a three or a four, we round up to five. If it ends in a six or a seven, we round down to five. And if it ends in an eight or a nine, we round up to ten. In our example, the total was thirty-three dollars and ninety cents. Since it already ends in a zero, no rounding is needed! But if the total had been thirty-three dollars and ninety-two cents, you would only pay thirty-three-ninety. If it was thirty-three-ninety-three, you’d pay thirty-three-ninety-five. The store does this for you, but knowing the rule means you can double-check the register!Learning to calculate tax and rounding isn’t just for tests; it’s a life skill. It helps you stay on budget and makes you a more confident person. Think about it: when you can do these calculations, you are the one in charge of the transaction. You know exactly where every cent is going. A major tip is to check your receipt. It will show you the “Subtotal,” which is the price before tax, the “HST,” which is the tax amount, and the “Total.” Sometimes it even shows the “Rounding” amount! Looking at receipts is a great way to practice your math. Try to find a receipt at home today and see if you can work backwards to find out what the tax percentage was. You are becoming a decimal master! We’ll see you in the next video, where we’ll use these totals to build a real budget!Before we go, remember that sales tax is different depending on where you are. Some provinces only have five percent tax, while others have fifteen! As an aware consumer, you should always know the tax rate of the place you are in. It’s part of your “geographic financial literacy.” Take a look at the shopping list in your lesson and try to estimate the 13% tax for each item. See how fast you can get! The more you practice, the easier it becomes. You’re doing great, and your math muscles are getting stronger every minute. Keep shopping, keep calculating, and we’ll see you soon!
