Convert 91% to a decimal:
[tex]91 \div 100 = 0.91[/tex]
Multiply the amount of people by this decimal:
[tex]1989 \times 0.91 = 1809.99[/tex]
Round the number to the nearest ones value:
1809.99
9 > 5
1809.99 -> 1810
1,810 people have reached the top of Mount Everest.
