Resources for Families
Unit 2: Decimals
Decimals most commonly show up in every day life when we are dealing with money.
Common mistakes to watch out for when your child is doing homework:
1. Placement of the decimal point. The most common mistakes with placement of the decimal point happen during multiplication. Compared to the other operations, multiplication is weird. You don't have to line up the decimal points and is the only operation the decimal doesn't simply get moved up or down into the correct position in the answer.
2. Changing the order of a subtraction problem. This most commonly happens with problems such as 5 - 3.96. Because the student sees that 5 is shorter, he/she changes the problem to 3.96 - 5. The easiest way to explain what to do, is to think of money. $5 is the same as $5.00. You don't magically have more money by adding the decimal point and two zeroes. However if you replace the 5 with 5.00 in the problem it makes a lot more sense 5.00 - 3.96.
Common mistakes to watch out for when your child is doing homework:
1. Placement of the decimal point. The most common mistakes with placement of the decimal point happen during multiplication. Compared to the other operations, multiplication is weird. You don't have to line up the decimal points and is the only operation the decimal doesn't simply get moved up or down into the correct position in the answer.
2. Changing the order of a subtraction problem. This most commonly happens with problems such as 5 - 3.96. Because the student sees that 5 is shorter, he/she changes the problem to 3.96 - 5. The easiest way to explain what to do, is to think of money. $5 is the same as $5.00. You don't magically have more money by adding the decimal point and two zeroes. However if you replace the 5 with 5.00 in the problem it makes a lot more sense 5.00 - 3.96.