`(0.72 xx 0.72 xx 0.72 - 0.39 xx 0.39 xx 0.39)/(0.72 xx 0.72 +0.72 xx 0.39 + 0.39 xx 0.39)` is equal to :

Options

A. 0.33
B. 0.45
C. 0.39
D. 0.36

Answer

To solve the expression \((0.72 \times 0.72 \times 0.72 - 0.39 \times 0.39 \times 0.39) / (0.72 \times 0.72 + 0.72 \times 0.39 + 0.39 \times 0.39)\), we will follow these steps:

### Step 1: Calculate \(0.72 \times 0.72 \times 0.72\)
First, we calculate \(0.72^3\):
\[ 0.72 \times 0.72 = 0.5184 \]
\[ 0.72 \times 0.5184 = 0.373248 \]
So, \(0.72^3 = 0.373248\).

### Step 2: Calculate \(0.39 \times 0.39 \times 0.39\)
Next, we calculate \(0.39^3\):
\[ 0.39 \times 0.39 = 0.1521 \]
\[ 0.39 \times 0.1521 = 0.059319 \]
So, \(0.39^3 = 0.059319\).

### Step 3: Calculate the numerator
Now we subtract the two results from Step 1 and Step 2:
\[ 0.373248 - 0.059319 = 0.313929 \]

### Step 4: Calculate \(0.72 \times 0.72\)
Now we calculate \(0.72 \times 0.72\) again:
\[ 0.72 \times 0.72 = 0.5184 \]

### Step 5: Calculate \(0.72 \times 0.39\)
Next, we calculate \(0.72 \times 0.39\):
\[ 0.72 \times 0.39 = 0.2808 \]

### Step 6: Calculate \(0.39 \times 0.39\)
Now we calculate \(0.39 \times 0.39\):
\[ 0.39 \times 0.39 = 0.1521 \]

### Step 7: Calculate the denominator
Now we add the results from Steps 4, 5, and 6:
\[ 0.5184 + 0.2808 + 0.1521 = 0.9513 \]

### Step 8: Final calculation
Now we divide the result from Step 3 by the result from Step 7:
\[ \frac{0.313929}{0.9513} \approx 0.329 \]

### Step 9: Rounding
Rounding \(0.329\) gives us approximately \(0.33\).

### Final Answer
Thus, the final answer is approximately \(0.33\).

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