What should be substracted from `-3/5` to get `7/10` ?

Answer

To solve the problem of what should be subtracted from \(-\frac{3}{5}\) to get \(\frac{7}{10}\), we can follow these steps:

### Step 1: Set up the equation
Let \(x\) be the number that we need to subtract from \(-\frac{3}{5}\). The equation can be set up as follows:
\[ -\frac{3}{5} - x = \frac{7}{10} \]

### Step 2: Rearrange the equation
To find \(x\), we can rearrange the equation:
\[ -x = \frac{7}{10} + \frac{3}{5} \]

### Step 3: Find a common denominator
To add the fractions on the right side, we need a common denominator. The denominators are 10 and 5. The least common multiple (LCM) of 10 and 5 is 10. We can convert \(-\frac{3}{5}\) to a fraction with a denominator of 10:
\[ -\frac{3}{5} = -\frac{3 \times 2}{5 \times 2} = -\frac{6}{10} \]

### Step 4: Add the fractions
Now we can add the fractions:
\[ -x = \frac{7}{10} - \frac{6}{10} = \frac{1}{10} \]

### Step 5: Solve for \(x\)
Now, we can solve for \(x\) by multiplying both sides by -1:
\[ x = -\frac{1}{10} \]

### Conclusion
Thus, the number that should be subtracted from \(-\frac{3}{5}\) to get \(\frac{7}{10}\) is:
\[ \boxed{-\frac{1}{10}} \]