Evaluate the following: `36. 36\ -\ 28. 4234\ -\ 7. 78\ +\ 7. 7`

Options

A. `7.8666`
B. `7.8696`
C. `7.8566`
D. `7.8646`

Answer

To evaluate the expression \(36.36 - 28.4234 - 7.78 + 7.7\), we can follow these steps:

### Step 1: Group the positive and negative terms
We can rearrange the expression to group the positive terms together and the negative terms together:
\[ (36.36 + 7.7) - (28.4234 + 7.78) \]

### Step 2: Convert all numbers to the same decimal places
To make addition and subtraction easier, we can convert \(7.7\) to \(7.70\) and \(7.78\) to \(7.7800\):
\[ (36.36 + 7.70) - (28.4234 + 7.7800) \]

### Step 3: Add the positive terms
Now, we will add the positive terms:
\[ 36.36 + 7.70 = 44.06 \]

### Step 4: Add the negative terms
Next, we will add the negative terms:
\[ 28.4234 + 7.7800 = 36.2034 \]

### Step 5: Subtract the sums
Now we can subtract the sum of the negative terms from the sum of the positive terms:
\[ 44.06 - 36.2034 \]

### Step 6: Perform the subtraction
To perform the subtraction:
\[ 44.0600 - 36.2034 = 7.8566 \]

### Final Answer
Thus, the final result of the expression \(36.36 - 28.4234 - 7.78 + 7.7\) is:
\[ \boxed{7.8566} \]