2004 AMC 12B Problem 1

Below is the professionally curated solution for Problem 1 of the 2004 AMC 12B, from LIVE by Po-Shen Loh. You can also try the full timed exam, view all 2004 AMC 12B solutions, or check the answer key.

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Concepts:geometric sequencework backwards

Difficulty rating: 900

1.

At each basketball practice last week, Jenny made twice as many free throws as she made at the previous practice. At her fifth practice she made 4848 free throws. How many free throws did she make at the first practice?

33

66

99

1212

1515

Solution:

Each practice she made twice the previous, so going backward we halve. From the fifth practice at 48,48, the earlier practices had 24,24, 12,12, 6,6, and 33 free throws.

Thus, the correct answer is A.

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