What is the resulting four-digit number when the tens digit and the thousands digit of 6789 are swapped?

• A. 8769
• B. 6789
• C. 8679
• D. 6798

Answer: (A)

Swapping the thousands place and the tens place means exchanging the digits in those two positions while leaving the other digits in place. In 6789, the thousands digit is 6 and the tens digit is 8. After swapping, the thousands place becomes 8 and the tens place becomes 6. The hundreds and ones digits stay 7 and 9, respectively. So the new digits from left to right are 8, 7, 6, 9, giving 8769.