Final answer:
To represent the number of people at the party, the equation 4 - (5/100) * 19 = 57 can be used.
Step-by-step explanation:
To write an equation that represents the number of people at the party, we can start by setting up an equation using the given information. From the equation 4 - 5% * 19 = 57, we can solve for the missing variable which represents the number of people at the party.
First, let's simplify the equation: 4 - (5/100) * 19 = 57.
Next, multiply 5/100 by 19 to get 0.95. Then subtract 0.95 from 4 to get 3.05. Therefore, there were 3.05 people at the party. Since you cannot have a fraction of a person, we can round this value to the nearest whole number. Hence, there were 3 people at the party.
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