What is the unit digit of `279 + 167 xx 342` ?

Options

A. `1`
B. `3`
C. `5`
D. `8`

Answer

To find the unit digit of the expression \( 279 + 167 \times 342 \), we can follow these steps:

### Step 1: Identify the unit digits
First, we identify the unit digits of the numbers involved in the expression:
- The unit digit of \( 279 \) is \( 9 \).
- The unit digit of \( 167 \) is \( 7 \).
- The unit digit of \( 342 \) is \( 2 \).

### Step 2: Calculate the unit digit of the multiplication
Next, we need to calculate the unit digit of \( 167 \times 342 \). We only need the unit digits for this calculation:
- The unit digit of \( 7 \times 2 \) is \( 14 \), and the unit digit of \( 14 \) is \( 4 \).

### Step 3: Add the unit digits
Now, we add the unit digit of \( 279 \) (which is \( 9 \)) to the unit digit of \( 167 \times 342 \) (which is \( 4 \)):
- So, we calculate \( 9 + 4 = 13 \).

### Step 4: Find the unit digit of the sum
The unit digit of \( 13 \) is \( 3 \).

### Conclusion
Thus, the unit digit of \( 279 + 167 \times 342 \) is \( 3 \).