Which number can replace both question marks?
`(4)/(?)=(?)/(100)`

Options

A. a)5
B. b)10
C. c)20
D. d)16

Explanation

To solve the equation \(\frac{4}{?} = \frac{?}{100}\), we can follow these steps:

### Step 1: Set up the equation
Let’s denote the unknown number that replaces the question mark as \(x\). Therefore, we can rewrite the equation as:
\[ \frac{4}{x} = \frac{x}{100} \]

### Step 2: Cross-multiply
To eliminate the fractions, we can cross-multiply:
\[ 4 \cdot 100 = x \cdot x \]
This simplifies to:
\[ 400 = x^2 \]

### Step 3: Solve for \(x\)
To find \(x\), we take the square root of both sides:
\[ x = \sqrt{400} \]
Calculating the square root gives:
\[ x = 20 \]

### Conclusion
Thus, the number that can replace both question marks is \(20\).

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