Answer:
30 additional teachers will have to be hired to reduce the ratio to 1:20.
Explanation:
Given that Jefferson School has 1800 students, and the teacher-pupil ratio is 1:30, to determine how many additional teachers will have to be hired to reduce the ratio to 1:20, the following calculation must be performed:
30 = 1800
1 = X
1800/30 = X
60 = X
20 = 1800
1 = X
1800/20 = X
90 = X
90 - 60 = 30
Therefore, 30 additional teachers will have to be hired to reduce the ratio to 1:20.