Newton’s Class

More than 93 percent of the students in Mr. Newton’s math class are girls. If Mr. Newton’s class has at least one boy, what is the least possible size of his class?
Source: mathcontest.olemiss.edu 2/24/2014

SOLUTION
Ratio    Percent
1:2\qquad 50.00
3:4\qquad 75.00
4:5\qquad 80.00
5:6\qquad 83.33
6:7\qquad 85.71
7:8\qquad 87.50
9:10\quad\:\: 90.00
10:11\quad\:\: 90.90
11:12\quad\:\: 91.67
12:13\quad\:\: 92.31
13:14\quad\:\: 92.86
14:15\quad\:\: 93.33
15:16\quad\:\: 93.75
16:17\quad\:\: 94.12
17:18\quad\:\: 94.44
\cdots
The least possible size of his class is 15.

Answer: 15

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About mvtrinh

Retired high school math teacher.
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