Answer: Choice C) x/600 = 55/100
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Step-by-step explanation:
The format is
part/whole = percent/100
the left side has "part" over "whole" as one fraction meaning we divide some small part over a larger number. In this case, we have x as the smaller part and 600 as the total number of messages. The letter x is the placeholder for Connor's amount of messages.
On the right side is 55/100 which turns into 55%. Recall that any percentage is basically that number over 100 since "percent" can be thought of as "per 100" (cent = 100)