Question

In the number 48.93, which digit is estimated?

1) 4
2) 8
3) 9
4) 3
5) None of the above, all digits are certain.

Answer 1

In the number 48.93, all digits are certain, and hence no digit is estimated. The concept of estimated digits or significant figures typically applies to contexts involving rounding or measurements, not to exact numbers like 48.93.

Step-by-step explanation:

In the number 48.93, none of the digits are estimated; all are certain. Each digit represents a specific value in the number's place value system, and there is no rounding or estimation involved. So, the correct answer is 5) None of the above, all digits are certain.

The question of which digit is estimated usually arises in the context of measurements or when rounding numbers to a certain degree of precision. For example, if we have the calculation 38.65 x 105.93, and we want the final answer limited to four significant figures, it would be 4,094. The rules for rounding come into play only when the calculation or measurement necessitates dropping some digits.

For instance, if we say that a number is 450, this has two significant figures by default, but to express it with four significant figures, we would write it as 450.0 or in scientific notation as 4.500 x 10². All significant figures are explicitly included in this representation.