x − a ll p eo pl e 5 2 x − m e n 5 2 x − 45 − c hi l d re n 3 ( 5 2 x − 45 ) − w o m e n x = 5 2 x + ( 5 2 x − 45 ) + ( 3 ( 5 2 x − 45 )) ∣ m y lt i pl y b y 5 5 x = 2 x + 2 x − 225 + 6 x − 675 5 x = 10 x − 900 ∣ s u b t r a c t 10 x − 5 x = − 900 ∣ d i v i d e b y − 5 x = 180 T h ere w ere 180 p eo pl e a t co n cer t .
There were 180 people at the concert. This was determined by setting up equations based on the information about men, women, and children at the concert and solving for the total number. The calculations involved relationships between the numbers of each group of attendees.
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