If + means `-: , xx ` means `- , -:` means ` xx` and - means + , then ` 8+ 6 xx 4 -: 3 -4 = ?`

Options

A. `-12`
B. `-20/3`
C. 12
D. `20/3`

Explanation

To solve the expression `8 + 6 xx 4 -: 3 - 4`, we first need to interpret the operations based on the definitions given in the question:

- `+` means `-` (subtraction)
- `xx` means `-` (subtraction)
- `-:` means `xx` (multiplication)
- `-` means `+` (addition)

Now, let's rewrite the expression using these definitions:

1. Replace `+` with `-`:
- `8 + 6` becomes `8 - 6`

2. Replace `xx` with `-`:
- `6 xx 4` becomes `6 - 4`

3. Replace `-:` with `xx`:
- `-: 3` becomes `xx 3` (which means multiplication by 3)

4. Replace `-` with `+`:
- `- 4` becomes `+ 4`

Now the expression looks like this:
`8 - 6 - 4 xx 3 + 4`

Next, we need to rewrite it again with the operations:
- `8 - 6` (subtraction)
- `- 4` (subtraction)
- `xx 3` (multiplication)
- `+ 4` (addition)

So the expression is now:
`8 - 6 - 4 * 3 + 4`

Now we can solve the expression step by step, following the order of operations (BODMAS/BIDMAS):

### Step 1: Perform the subtraction
Calculate `8 - 6`:
- \( 8 - 6 = 2 \)

### Step 2: Substitute back into the expression
Now we have:
`2 - 4 xx 3 + 4`

### Step 3: Perform the multiplication
Calculate `4 xx 3` (which is `4 - 3`):
- \( 4 - 3 = 1 \)

### Step 4: Substitute back into the expression
Now we have:
`2 - 1 + 4`

### Step 5: Perform the subtraction
Calculate `2 - 1`:
- \( 2 - 1 = 1 \)

### Step 6: Substitute back into the expression
Now we have:
`1 + 4`

### Step 7: Perform the addition
Calculate `1 + 4`:
- \( 1 + 4 = 5 \)

Thus, the final answer is:
**5**