`72 xx 28 = 36 xx 4 xx` ........ The number in the blank is
(A) multiple of 7
(B) a prime number
(C) less than 10
(D) an even number
E factor of 56
Which of the following is correct?

Options

A. (A), (D), (E)
B. (A), (B), (C)
C. (A), (D), (B)
D. (C), (D), (E)

Explanation

To solve the equation \( 72 \times 28 = 36 \times 4 \times x \), we will first calculate the left-hand side and then solve for \( x \).

### Step 1: Calculate \( 72 \times 28 \)

First, we need to calculate \( 72 \times 28 \).

\[ 72 \times 28 = 2016 \]

### Step 2: Calculate \( 36 \times 4 \)

Next, we calculate \( 36 \times 4 \).

\[ 36 \times 4 = 144 \]

### Step 3: Set up the equation

Now we can set up the equation based on the values we calculated:

\[ 2016 = 144 \times x \]

### Step 4: Solve for \( x \)

To find \( x \), we divide both sides of the equation by \( 144 \):

\[ x = \frac{2016}{144} \]

Calculating this gives:

\[ x = 14 \]

### Step 5: Analyze the options

Now we need to analyze the number \( 14 \) based on the options provided:

1. **Multiple of 7**: Yes, \( 14 = 7 \times 2 \).
2. **Prime number**: No, \( 14 \) is not a prime number (it has divisors other than 1 and itself).
3. **Less than 10**: No, \( 14 \) is greater than 10.
4. **Even number**: Yes, \( 14 \) is even (it is divisible by 2).
5. **Factor of 56**: Yes, \( 14 \) is a factor of \( 56 \) (since \( 14 \times 4 = 56 \)).

### Conclusion

Based on the analysis, the correct options are:
- A (multiple of 7)
- D (even number)
- E (factor of 56)

Thus, the answer is **A, D, and E**.