Solve: `0.4(a+1.4)=0.72`

Answer

To solve the equation \( 0.4(a + 1.4) = 0.72 \), we will follow these steps:

### Step 1: Distribute the 0.4
Start by distributing \( 0.4 \) to both terms inside the parentheses:

\[ 0.4a + 0.4 \times 1.4 = 0.72 \]

Calculating \( 0.4 \times 1.4 \):

\[ 0.4 \times 1.4 = 0.56 \]

So, the equation becomes:

\[ 0.4a + 0.56 = 0.72 \]

### Step 2: Isolate the term with \( a \)
Now, we need to isolate the term with \( a \) by subtracting \( 0.56 \) from both sides:

\[ 0.4a + 0.56 - 0.56 = 0.72 - 0.56 \]

This simplifies to:

\[ 0.4a = 0.16 \]

### Step 3: Solve for \( a \)
Next, we solve for \( a \) by dividing both sides by \( 0.4 \):

\[ a = \frac{0.16}{0.4} \]

Calculating the division:

\[ a = 0.4 \]

### Final Answer
Thus, the solution to the equation is:

\[ \boxed{0.4} \]

---