Answer:
11%
Explanation:
The full circle graph represents 100% of the given population. All populations are given except for "three or more." Adding all percentages of each population should add up to 100%.
No absences (none): 23%
One absence: 45%
Two absences: 21%
Three more absences: unknown.
Let the variable x represent the unknown population.
23% + 45% + 21% + x = 100%
Combine like terms.
89% + x = 100%
Subtract 89% from both sides.
x = 11%
To put it more simply, subtract all the percentages from 100% to get the percent of the missing population. 100 - 23 - 45 - 21 = 11