<PRE><B>Question 1050947</B>
90% of 100% = 9/10

Answer to part A is {{{9/10}}}.

10% of 100% = 1/10

Answer to part B is {{{1/10}}}

CHECK
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90% of 400 = 360 infected people
360/400 = 9/10
Every 9 of 10 people are infected.

10% of 400 = 40 infected people
40/400 = 1/10
Every 1 of 10 people are not infected.</PRE>