Final answer:
Roberto has completed 61% of the marathon when rounding to the nearest whole number after running 16 out of 26.2 miles.
Step-by-step explanation:
To calculate the percent of the marathon that Roberto has completed, we need to divide the distance he has run by the total distance of the marathon and then multiply by 100 to get the percentage. Roberto has run 16 miles of the 26.2 miles in the marathon.
First, we divide the distance run by the total distance:
(Distance run ÷ Total distance) × 100 = Percentage completed
(16 miles ÷ 26.2 miles) × 100 = 61.0687023%
Rounded to the nearest whole number, Roberto has completed 61% of the marathon.