Learn how to add and subtract decimals in a few simple steps.

## Step by step guide to add and subtract decimals

1. Line up the numbers.
2. Add zeros to have the same number of digits for both numbers if necessary.

### Example 1:

Add. $$1.5 \ + \ 2.14=$$

Solution:

First line up the numbers: $$\begin{array}{r} &1.5\\ +\!\!\!\!\!\!&2.14\\ \hline \end{array}→$$ Add zeros to have same number of digits for both numbers. $$\begin{array}{r} &1.50\\ +\!\!\!\!\!\!&2.14\\ \hline \end{array}$$, Start with the hundredths place. $$0 \ + \ 4=4$$, $$\begin{array}{r} &1.50\\ +\!\!\!\!\!\!&2.14 \\ \hline \end{array} \\ \ \ \ \ \ \ \ \ \ \ 4$$ , Continue with tenths place. $$5 \ + \ 1=6$$, $$\begin{array}{r} &1.50\\ +\!\!\!\!\!\!&2.14 \\ \hline \end{array} \\ \ \ \ \ \ \ \ \ \ \ .64$$. Add the ones place. $$2 \ + \ 1=3$$, $$\begin{array}{r} &1.50\\ +\!\!\!\!\!\!&2.14 \\ \hline \end{array} \\ \ \ \ \ \ \ \ 3.64$$

### Example 2:

Subtract decimals. $$2.56 \ – \ 1.15= \begin{array}{r} &2.56\\ – \!\!\!\!\!\!&1.15\\ \hline \end{array}$$

Solution:

Start with the hundredths place. $$6 \ – \ 5=1$$, $$2.56 \ – \ 1.15= \begin{array}{r} &2.56\\ – \!\!\!\!\!\!&1.15\\ \hline \end{array}$$ continue with tenths place. $$5 – 1=4$$
$$\begin{array}{r} &2.56\\ – \!\!\!\!\!\!&1.15 \\ \hline \end{array} \\ \ \ \ \ \ \ \ 0.41$$, subtract the ones place. $$2-1=1$$, $$\begin{array}{r} &2.56\\ – \!\!\!\!\!\!&1.15 \\ \hline \end{array} \\ \ \ \ \ \ \ \ 1.41$$

### Example 3:

Add. $$2.5 \ + \ 1.24=$$

Solution:

First line up the numbers: $$\begin{array}{r} &2.5\\ +\!\!\!\!\!\!&1.24\\ \hline \end{array}→$$ Add zeros to have same number of digits for both numbers. $$\begin{array}{r} &2.50\\ +\!\!\!\!\!\!&1.24\\ \hline \end{array}$$, Start with the hundredths place. $$0 \ + \ 4=4$$, $$\begin{array}{r} &2.50\\ +\!\!\!\!\!\!&1.24 \\ \hline \end{array} \\ \ \ \ \ \ \ \ \ \ \ 4$$, Continue with tenths place. $$5 \ + \ 2=7$$, $$\begin{array}{r} &2.50\\ +\!\!\!\!\!\!&1.24 \\ \hline \end{array} \\ \ \ \ \ \ \ \ \ \ .74$$ . Put the decimal point and add the ones place. $$2 \ + \ 1=3$$, $$\begin{array}{r} &2.50\\ +\!\!\!\!\!\!&1.24 \\ \hline \end{array} \\ \ \ \ \ \ \ \ 3.74$$

### Example 4:

Subtract decimals. $$4.67 \ – \ 2.15= \begin{array}{r} &4.67\\ – \!\!\!\!\!\!&2.15\\ \hline \end{array}$$

Solution:

Start with the hundredths place. $$7 \ – \ 5=2$$, $$\begin{array}{r} &4.67\\ – \!\!\!\!\!\!&2.15\\ \hline \end{array} \\ \ \ \ \ \ \ \ 2$$, continue with tenths place. $$6 \ – \ 1=5$$, $$\begin{array}{r} &4.67\\ – \!\!\!\!\!\!&2.15\\ \hline \end{array} \\ \ \ \ \ \ \ \ \ \ \ .52$$, put the decimal point and subtract the ones place. $$4 \ – \ 2 =2$$, $$\begin{array}{r} &4.67\\ – \!\!\!\!\!\!&2.15\\ \hline \end{array} \\ \ \ \ \ \ 2.52$$

## Exercises

$$\color{blue}{ \begin{array}{r} &15.14\\ -\!\!\!\!\!\!&12.18\\ \hline \end{array} }$$

$$\color{blue}{ \begin{array}{r} &65.72\\ +\!\!\!\!\!\!&43.67\\ \hline \end{array} }$$

$$\color{blue}{ \begin{array}{r} &82.56\\ +\!\!\!\!\!\!&12.28\\ \hline \end{array} }$$

$$\color{blue}{ \begin{array}{r} &34.18\\ -\!\!\!\!\!\!&23.45\\ \hline \end{array} }$$

$$\color{blue}{ \begin{array}{r} &90.37\\ +\!\!\!\!\!\!&56.97\\ \hline \end{array} }$$

$$\color{blue}{ \begin{array}{r} &45.78\\ -\!\!\!\!\!\!&23.39\\ \hline \end{array} }$$

• $$\color{blue}{2.96}$$
• $$\color{blue}{109.39}$$
• $$\color{blue}{94.84}$$
• $$\color{blue}{10.73}$$
• $$\color{blue}{147.34}$$
• $$\color{blue}{22.39}$$