What should come in place of the question mark (?) in the following questions ?
`1255.5 ÷ (18 xx 15.5) = ?`

Options

A. 5.5
B. 6.5
C. 4.5
D. 3.5

Answer

To solve the equation \( 1255.5 ÷ (18 \times 15.5) = ? \), we will follow these steps:

### Step 1: Calculate the product inside the parentheses
First, we need to calculate \( 18 \times 15.5 \).

\[ 18 \times 15.5 = 279 \]

### Step 2: Divide 1255.5 by the result from Step 1
Now we will divide \( 1255.5 \) by \( 279 \).

\[ 1255.5 ÷ 279 \]

To perform the division, we can convert \( 1255.5 \) into a fraction:

\[ 1255.5 = \frac{12555}{10} \]

Now, we can rewrite the division:

\[ \frac{12555}{10} ÷ 279 = \frac{12555}{10} \times \frac{1}{279} = \frac{12555}{10 \times 279} \]

Calculating \( 10 \times 279 \):

\[ 10 \times 279 = 2790 \]

So, we have:

\[ \frac{12555}{2790} \]

### Step 3: Simplify the fraction
Now we need to simplify \( \frac{12555}{2790} \). We can find the greatest common divisor (GCD) of \( 12555 \) and \( 2790 \) to simplify.

Using the Euclidean algorithm or prime factorization, we find that the GCD is \( 9 \).

Now, we divide both the numerator and denominator by \( 9 \):

\[ \frac{12555 ÷ 9}{2790 ÷ 9} = \frac{1395}{310} \]

### Step 4: Perform the final division
Now we can perform the division \( 1395 ÷ 310 \):

\[ 1395 ÷ 310 = 4.5 \]

Thus, the final answer is:

\[ ? = 4.5 \]

### Final Answer:
The value that should come in place of the question mark is \( 4.5 \).

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