How many ones are there in the sum of 23 + 53?

The correct answer is: 6

Place value is the value of each digit in a number. For example, the 5 in 350 represents 5 tens, or 50; however, the 5 in 5,006 represents 5 thousands, or 5,000.
Here 23 + 53 with place values can be written as :
    2 (tens) 3(ones)
+ 5 (tens) 3(ones)
In the question we've only been asked for numbers in ones places so adding the numbers in one's places we get:
 3 (ones)
+ 3(ones)
______
6(ones)
Thus, there are 6 ones in the sum of 23 and 53.