Answer:
70 -20x = 60 -15x
Step-by-step explanation:
The amount of money left on Josh's card is ...
70 -20x
The amount of money left on Jessica's card is ...
60 -15x
These amounts are the same when ...
70 -20x = 60 -15x
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<em>Additional comment</em>
The solution to this equation is ...
10 = 5x ⇒ x = 2 . . same amount after purchase of 2 pizzas
Multiples of 10 = 10, 20, 30, 40, 50, 60
This means the 10th, 20th, 30th, 40th, 50th, 60th, ... fan will get a free hat.
Multiples of 12 = 12, 24, 36, 48, 60
This means the 12th, 24th, 36th, 48th, 60th, ... fan will get a free shirt.
So the 60th fan will receive both a hat and a shirt.
Meaning 60 fans will come to the stadium before a fan receives both a hat and a shirt.