Fill in the missing fractions :
`7/10-square=3/10`

Answer

To solve the equation \( \frac{7}{10} - \text{square} = \frac{3}{10} \), we need to find the missing fraction (the value of "square"). Here’s how to do it step by step:

### Step 1: Write the equation
We start with the equation:
\[ \frac{7}{10} - \text{square} = \frac{3}{10} \]

### Step 2: Isolate the missing fraction
To find the missing fraction, we can isolate it by moving \( \frac{3}{10} \) to the left side of the equation. We do this by adding \( \frac{3}{10} \) to both sides:
\[ \frac{7}{10} - \text{square} + \frac{3}{10} = \frac{3}{10} + \frac{3}{10} \]
This simplifies to:
\[ \frac{7}{10} - \text{square} = \frac{3}{10} \]

### Step 3: Rewrite the equation
Now we can rewrite the equation:
\[ \frac{7}{10} - \frac{3}{10} = \text{square} \]

### Step 4: Subtract the fractions
Since both fractions have the same denominator, we can subtract the numerators:
\[ \frac{7 - 3}{10} = \text{square} \]
Calculating the numerator gives us:
\[ \frac{4}{10} = \text{square} \]

### Step 5: Simplify the fraction
Now we can simplify \( \frac{4}{10} \):
\[ \frac{4 \div 2}{10 \div 2} = \frac{2}{5} \]

### Final Answer
Thus, the missing fraction is:
\[ \text{square} = \frac{2}{5} \]

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