Answer:
Conrad had 56 sales on Monday , 168 sales on Tuesday and 504 sales on Wednesday.
Step-by-step explanation:
Let x be the no. of sales on Monday
We are given that On Tuesday Conrad had 3 times as many sales as on Monday.
So, Conrad had sales on Tuesday = 3x
We are also given that On Wednesday, he had 9 times as many sales as on Monday.
So, Conrad had sales on Wednesday = 9x
Over the three days, he had a total of 728 sales
So, x+3x+9x=728
13x=728
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x=56
Conrad had sales on Tuesday = 3x =3(56)=168
Conrad had sales on Wednesday = 9x=9(56)=504
Hence Conrad had 56 sales on Monday , 168 sales on Tuesday and 504 sales on Wednesday.