Adding Decimals Explained: A Step-By-Step Review | Understanding Decimal Addition

welcome to math with mr j in this video i'm going to go through a quick review of adding decimals this should be helpful for anyone looking for a quick refresher whether you're in middle school high school college continuing your education as an adult really no matter what class or goal you are working towards here are a couple of examples to get this down let's jump into number one where we have 9 and 6 10 plus 3 and 87 hundredths now when we add decimals the first thing that we want to do we want to line the problem up correctly and we do that by lining the decimals up that's going to line up all of our places so let's rewrite this problem vertically so up and down underneath here 9 and 6 10 plus three and eighty-seven hundredths so our decimals are lined up that means our places are going to be lined up now the problem does look a little offset because nine and six tenths goes to the tenths place and then three and eighty-seven hundredths goes to the hundredths place so what we can do here to make this look more lined up we can use placeholder zeros remember zeros to the right of a decimal do not change the value of that decimal so we're going to be working with an equivalent decimal we're not changing the value of the problem at all so we're able to use placeholder zeros to the right of a decimal so let's put a zero here in the hundredths place and now both of our numbers go to the hundredths and we're able to add so we'll start with the hundredths zero plus seven is seven then we'll move to the tenths six plus eight is fourteen so we carry our one now our decimal goes straight down into our answer it's lined up throughout the entire problem now we'll move to the ones place where we have one plus nine plus three one plus nine is ten plus three is thirteen so we'll put our three and then our carried one will be brought straight down and we end up with 13 and 47 hundredths let's move on to number two where we have 124 and 792 thousandths plus 84 and 5 tenths so let's line our decimals up here 124 and 792 thousandths plus 84 and 5 tenths so let's use placeholder zeros to line this up a little better here a zero in the hundredths and then a zero in the thousandths again zeros to the right of a decimal do not change the value of that decimal it's an equivalent decimal so we're able to use those placeholder zeros now we can add so we'll start with the thousandths place two plus zero is two the hundredths place nine plus zero is nine the tenths place seven plus five is twelve so we'll put our two and then carry the one we can bring our decimal straight down into the answer now we have the ones place one plus four is five plus four is nine the tens place two plus eight is ten so we'll put our zero here carry the one and then the hundreds place one plus one is 2. so we end up with 209 and 292 thousandths so there you have it there's a quick review of adding decimals line the decimals up use placeholder zeros if need be and then add i hope that helped thanks so much for watching until next time peace you