1. In which of the following numbers is the digit 1 in the ten thousands place and the digit 9 in the ones place? Select ALL that apply.
Answer: A,B
12,679 and 12,769 have the digit 1 in the ten thousands place and the digit 9 in the ones place.
Both 12,679 and 12,769 meet the criteria of having the digit 1 in the ten thousands place and the digit 9 in the ones place.
A) 12,679
This number has the digit 1 in the ten thousands place (1) and the digit 9 in the ones place (9), fulfilling both conditions set by the question.
B) 12,769
Similar to option A, this number also contains the digit 1 in the ten thousands place (1) and the digit 9 in the ones place (9), making it another correct choice.
C) 12,796
Although this number has the digit 1 in the ten thousands place (1), it has the digit 6 in the ones place instead of 9. Therefore, it does not satisfy the criteria and is incorrect.
D) 21,679
In this case, the digit 1 is not in the ten thousands place (it is in the thousands place), and the digit 9 is in the ones place. Thus, this number does not meet the specified conditions and is incorrect.
E) 21,769
Like option D, the digit 1 is in the thousands place rather than the ten thousands place, and the digit 9 is in the ones place. Consequently, this option does not fulfill the requirements and is incorrect.
F) 21,796
This number also places the digit 1 in the thousands place, failing to meet the requirement for the ten thousands place. As such, it is also incorrect.
Conclusion
The numbers 12,679 and 12,769 are the only ones that correctly have the digit 1 in the ten thousands place and the digit 9 in the ones place. All other options either misplace the digit 1 or do not have 9 in the appropriate position, confirming that the correct answers are A and B.