Step 1a

Start with the ones (or units) digit. Add 8 and 9, which gives you 17.

Write down the one digit of the result, which is 7, and carry over the tens digit (since 17 is greater than 9).

Move on to the tens digit. Add 1 (the carried-over digit) to 6 and 2, which gives you 9.

Move on to the hundreds digit. Add 2 and 3, which gives you 5.

So the final answer is 597.

Therefore, 268 + 329 = 597.

Explanation: Here, after adding the numbers, the result is 597.

Step 2a

Roopa has 173 pens

Chaitra has 242 pens

Therefore, the total number of pens they both have is:

173 + 242 = 415 pens.

Explanation: Here, we added both numbers of pens resulting in a total of 415 pens.