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5th grade

Course: 5th grade > Unit 2

Lesson 2: Adding decimals intro
Math
5th grade
Add decimals
Adding decimals intro
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Adding decimals

Google Classroom
Start with simple problems like 0.2 + 0.4 and build to more complex problems like 10.3 + 36.75.
This article is designed to help you learn how to add decimals by letting you jump in and give it a try without being shown how to do it first.
The problems go from easier to more difficult, and along the way, there are examples and explanations for the times you get stuck. You'll learn the most if you look at the times you're confused as chances to learn!
Let's start by adding two tenths together.

Section 1: Adding tenths less than one

Problem 1a
0.5+0.4=
  • Your answer should be
  • an integer, like 6
  • a simplified proper fraction, like 3/5
  • a simplified improper fraction, like 7/4
  • a mixed number, like 1 3/4
  • an exact decimal, like 0.75
  • a multiple of pi, like 12 pi or 2/3 pi

Beautiful, let's move on to problems with whole numbers and tenths.

Section 2: Adding whole numbers and tenths

Problem 2a
6.4+2=
  • Your answer should be
  • an integer, like 6
  • a simplified proper fraction, like 3/5
  • a simplified improper fraction, like 7/4
  • a mixed number, like 1 3/4
  • an exact decimal, like 0.75
  • a multiple of pi, like 12 pi or 2/3 pi

Excellent, next up are problems where both numbers have a whole number and a tenth.

Section 3: Adding tenths greater than one

Problem 3a
3.7+22.1=
  • Your answer should be
  • an integer, like 6
  • a simplified proper fraction, like 3/5
  • a simplified improper fraction, like 7/4
  • a mixed number, like 1 3/4
  • an exact decimal, like 0.75
  • a multiple of pi, like 12 pi or 2/3 pi

Rockin'! Let's move on to adding hundredths.

Section 4: Adding hundredths

Problem 4a
0.31+0.64=
  • Your answer should be
  • an integer, like 6
  • a simplified proper fraction, like 3/5
  • a simplified improper fraction, like 7/4
  • a mixed number, like 1 3/4
  • an exact decimal, like 0.75
  • a multiple of pi, like 12 pi or 2/3 pi

Sweet, now we're ready to solve problems with hundredths, tenths, and whole numbers.

Section 5: Adding whole numbers, tenths, and hundredths

Problem 5a
42+4.27=
  • Your answer should be
  • an integer, like 6
  • a simplified proper fraction, like 3/5
  • a simplified improper fraction, like 7/4
  • a mixed number, like 1 3/4
  • an exact decimal, like 0.75
  • a multiple of pi, like 12 pi or 2/3 pi

Great, let's finish with a few more challenging problems.

Section 6: Challenge problems

Problem 6a
2.59+5.16=
  • Your answer should be
  • an integer, like 6
  • a simplified proper fraction, like 3/5
  • a simplified improper fraction, like 7/4
  • a mixed number, like 1 3/4
  • an exact decimal, like 0.75
  • a multiple of pi, like 12 pi or 2/3 pi

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