SOLUTION: Please help me solve this problem: A school has 900 students. The ratio of students to teachers is 25:1. How many more teachers are needed to have a ratio of 20:1?

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Question 1082016: Please help me solve this problem: A school has 900 students. The ratio of students to teachers is 25:1. How many more teachers are needed to have a ratio of 20:1?
Answer by josgarithmetic(39616) About Me  (Show Source):
You can put this solution on YOUR website!
t, teachers to hire
x%2F900=1%2F25, ONE teacher for twentyfive students

900%2F25=36, teachers already present


%28t%2B36%29%2F900=1%2F20-----the ratio wanted

t=900%2F20-36
t=45-36
highlight%28t=9%29