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2007 AMC 10B Problem 8

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2007 AMC 10B Problem 8AMC 10 Step by Step

Name: Date: September 13, 2026

Basic Counting · difficulty 2 of 5 · about 3 min · position P1-10

On the trip home from the meeting where this AMC10 was constructed, the Contest Chair noted that his airport parking receipt had digits of the form $bbcac,$ where $0 \le a < b < c \le 9,$ and $b$ was the average of $a$ and $c.$ How many different five-digit numbers satisfy all these properties?

A)
$12$
B)
$16$
C)
$18$
D)
$20$
E)
$25$

2007 AMC 10B Problem 8

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