Replace `'square'` in each of the following by the correct number :
`3""2/5=square/15`

Answer

To solve the equation \( 3 \frac{2}{5} = \frac{\text{square}}{15} \), we need to find the value of "square". Let's go through the steps:

### Step 1: Convert the mixed fraction to an improper fraction
The mixed fraction \( 3 \frac{2}{5} \) can be converted to an improper fraction.

To do this:
- Multiply the whole number (3) by the denominator (5):
\( 3 \times 5 = 15 \)
- Add the numerator (2) to this result:
\( 15 + 2 = 17 \)

So, \( 3 \frac{2}{5} = \frac{17}{5} \).

### Step 2: Set up the equation
Now we can rewrite the equation:
\[ \frac{17}{5} = \frac{\text{square}}{15} \]

### Step 3: Cross-multiply to solve for "square"
Cross-multiplying gives us:
\[ 17 \times 15 = \text{square} \times 5 \]

Calculating \( 17 \times 15 \):
\[ 17 \times 15 = 255 \]

So, we have:
\[ 255 = \text{square} \times 5 \]

### Step 4: Solve for "square"
Now, divide both sides by 5 to isolate "square":
\[ \text{square} = \frac{255}{5} \]

Calculating \( \frac{255}{5} \):
\[ \frac{255}{5} = 51 \]

### Final Answer
Thus, the value of "square" is \( 51 \).

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