Question

While rounding off, if the digit to be dropped is less than $5$, then the preceding digit:

• A. increases by $1$
• B. remains unchanged
• C. decreases by $1$
• D. None of the above

Answer 1

Answer: (B)

When rounding, you examine the digit following (i.e., to the right of) the digit that is to be the last digit in the rounded off number. The digit you are examining is the first digit to be dropped.

1. If that first digit to be dropped is less than $5$ (that is, $1,2,3$ or $4$), drop it, and also drop all the digits to the right of it.
   
2. If that first digit to be dropped is more than $5$ (that is, $6,7,8$ or $9$), increase by 1 the number to be rounded, that is, the preceeding digit (to the digit being dropped).

Thus, in our case, since the digit to be dropped is less than $5$, we make no change to the preceding digit.