Basic Decimals: Lessons and Problems
Children commonly are introduced to decimals in fourth grade, after learning about fractions in third grade. Since decimals and fractions both represent parts of a whole, kids who understand fractions can typically grasp decimals. Read on for ways to help your child learn basic decimal concepts.
How Can My Child Learn Decimal Concepts?
Place Values and How to Read Decimals
Start by reviewing the place values of whole numbers. Beginning at the right and moving to the left, they are ones, tens, hundreds, thousands, ten thousands, hundred thousands and millions. Decimal place values begin at the decimal point and move to the right. Most fourth graders learn tenths and hundredths.
When learning to read decimals, start by reviewing whole numbers. Your child should read 762 as 'seven hundred sixtytwo,' not 'seven hundred and sixtytwo.' The decimal point is read as 'and.' So 6.3 is read as 'six and three tenths.' A larger decimal, such as 8.43, is read as 'eight and fortythree hundredths.'
Changing Decimals to Fractions
Show your child that if the decimal is .1, it is read as 'one tenth' and written as 1/10. If you have .43, you would write the fraction 43/100, because it's read as 'fortythree hundredths.'
Adding and Subtracting Decimals
Adding decimals is like doing regular addition; just be careful to line up the decimal points. The place values, both before and after the decimal point, also line up. The decimal point is also placed in its column in the answer.
Subtracting decimals follows the same process as adding them. Line up the decimal points and subtract like you would any other numbers. Just remember to bring down the decimal in the answer.
Multiplying Decimals
For multiplication, decimal points are not lined up as in addition and subtraction. The numbers are lined up so that those at the right end are in the same column. However, the decimals are written in the numbers. Multiply as for whole numbers.
So the work for 15.3 x 3.21 will look just the same as for 153 x 321. Once you have the answer (49,113), look at the decimal numbers and count how many numbers in all follow decimal points. There is one in 15.3 and two in 3.21. The total of numbers that follow decimal points is 1 + 2, or 3. Put the decimal point in front of the third number from the right so that the answer is 49.113.
Dividing Decimals
When you divide a decimal by a whole number, there is one difference from standard division. In the answer position, you put the decimal point exactly above the decimal point in the dividend (the number being divided). Ignore that decimal point until you finish working the problem; it is then part of the answer.
When you divide a decimal number by another decimal number, the first thing you need to do is turn the divisor (the number that divides into the dividend) into a whole number. You do this by moving the decimal point to the right side of the number. So in the problem 6.54 ÷ .2, you change .2 to 2.
Just like working with fractions, what you do to one number is done to all the numbers. Since you moved the decimal point one number to the right in the divisor, you have to do that in the dividend also. Therefore 6.54 become 65.4. You show these movements by using a ^ symbol where the new decimals will be. Then you can divide the new decimal by the new whole number.
For the problem 6.75 ÷ .25, you would change the .25 to 25. Since you moved the decimal point two numbers to the right, you would do the same for 6.75 to make it 675. The problem is now 675 ÷ 25.
Practice Decimal Problems
1. How would you read 9.56? Write it out.
2. Convert these decimals into fractions:
 .4
 .72
 .9
 .98
3. Solve the following problems (round to the nearest hundredth if necessary):
 3.6 + 5.4
 8.34 + 7.22
 5.8  2.6
 6.93  .51
 2.7 x 9.1
 4.5 x 6.7
 3.4 x 8.7
 6.2 ÷ 4
 7.75 ÷ 2.25
 4.4 ÷ 2.2
Answer Key
1. Nine and fiftysix hundredths
2. Convert these decimals into fractions:
 4/10
 72/100
 9/10
 98/100
3. Solve the following problems (round to the nearest hundredth if necessary):
 9
 15.56
 3.2
 6.42
 24.57
 30.15
 29.58
 1.55
 3.44
 2
Other Articles You May Be Interested In

The decimal numbering system is the basis for modern number theory. Read on to learn how to help your children understand decimal places, percentages, and place values.

Place values and decimal mathematics can be confusing, but the way to master decimals is to first learn how place values work. By learning place values and decimals, your child will be able to better understand the math concepts they will learn in middle and high school.
We Found 7 Tutors You Might Be Interested In
Huntington Learning
 What Huntington Learning offers:
 Online and incenter tutoring
 One on one tutoring
 Every Huntington tutor is certified and trained extensively on the most effective teaching methods
K12
 What K12 offers:
 Online tutoring
 Has a strong and effective partnership with public and private schools
 AdvancEDaccredited corporation meeting the highest standards of educational management
Kaplan Kids
 What Kaplan Kids offers:
 Online tutoring
 Customized learning plans
 RealTime Progress Reports track your child's progress
Kumon
 What Kumon offers:
 Incenter tutoring
 Individualized programs for your child
 Helps your child develop the skills and study habits needed to improve their academic performance
Sylvan Learning
 What Sylvan Learning offers:
 Online and incenter tutoring
 Sylvan tutors are certified teachers who provide personalized instruction
 Regular assessment and progress reports
Tutor Doctor
 What Tutor Doctor offers:
 InHome tutoring
 One on one attention by the tutor
 Develops personlized programs by working with your child's existing homework
TutorVista
 What TutorVista offers:
 Online tutoring
 Student works oneonone with a professional tutor
 Using the virtual whiteboard workspace to share problems, solutions and explanations