Rounding 4,241,933,200 to a single digit times a power of 10 would result in:
4.2 × 10^9
To round to this value, we drop all the digits after the tens digit (which is 2), and then round the tens digit up to 3 because the digit to its right (which is 9) is greater than or equal to 5. Finally, we append nine zeros to the end of the number to represent the power of 10.