Answer:
Lenny purchased 45 bricks
Step-by-step explanation:
let's call the total amount of bricks x.
(equation) 10x + 20 = 470.
10x = 470-20
10x = 450
x = 45.
Lenny purchased 45 bricks.
Goodluck on your schoolwork/homework!
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sorry for any errors or bad explanations.