Solve : `14.78 - 3.6 [2.5 - (1.4 - 0.9)]`

Answer

Let's solve the expression step by step:

**Given Expression:**
\[ 14.78 - 3.6 [2.5 - (1.4 - 0.9)] \]

### Step 1: Solve the innermost brackets
First, we need to solve the expression inside the innermost brackets:
\[ 1.4 - 0.9 \]

**Calculation:**
\[ 1.4 - 0.9 = 0.5 \]

### Step 2: Substitute back into the expression
Now substitute \( 0.5 \) back into the expression:
\[ 14.78 - 3.6 [2.5 - 0.5] \]

### Step 3: Solve the next set of brackets
Next, we solve the expression inside the square brackets:
\[ 2.5 - 0.5 \]

**Calculation:**
\[ 2.5 - 0.5 = 2.0 \]

### Step 4: Substitute back into the expression
Now substitute \( 2.0 \) back into the expression:
\[ 14.78 - 3.6 [2.0] \]

### Step 5: Multiply
Now, we need to multiply \( 3.6 \) by \( 2.0 \):
\[ 3.6 \times 2.0 \]

**Calculation:**
\[ 3.6 \times 2.0 = 7.2 \]

### Step 6: Substitute back into the expression
Now substitute \( 7.2 \) back into the expression:
\[ 14.78 - 7.2 \]

### Step 7: Final Calculation
Now, we perform the final subtraction:
\[ 14.78 - 7.2 \]

To make the subtraction easier, we can convert \( 7.2 \) to \( 7.20 \):
\[ 14.78 - 7.20 = 7.58 \]

### Final Answer
The final answer is:
\[ \boxed{7.58} \]

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