AMC 8 · 2002 · #4

Grade 4 number-theory
digit-constraintsplace-valuepattern-recognitionsystematic-enumeration systematic-enumerationpattern-recognition ↑ Prerequisites: place-valuemulti-digit-arithmetic
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Problem
The year 2002 reads the same forward and backward, so it is a palindrome. Find the next year after 2002 that is also a palindrome, then multiply its four digits together.

Pick an answer.

(A)
0
(B)
4
(C)
9
(D)
16
(E)
25

AMC 8 2002 problem © Mathematical Association of America (MAA AMC). Reproduced for educational use.

How to solve
Strategy Look for a Pattern

A 4-digit palindrome always has the shape ABBA — the thousands digit matches the units digit, and the hundreds digit matches the tens digit. Tool #5 (Look for a Pattern) captures that shape. Once we lock the shape in, Tool #6 (Guess and Check) finishes the job: keep A = 2 to stay close to 2002, and try the next value of B.

1STEP 1

A four-digit palindrome must read ABBA — the thousands digit matches the units, the hundreds the tens.

palindrome year = ABBA
2STEP 2

Fit 2002 to ABBA: A = 2, B = 0, and the tens digit 0 and units digit 2 confirm the pattern.

2002 = ABBA with A = 2, B = 0
3STEP 3

Keep A = 2 and raise B from 0 to 1 (making A = 3 would jump all the way to 3003), which gives 2112.

A = 2, B = 1 → ABBA = 2112
4STEP 4

Multiply the four digits of 2112.

2 × 1 × 1 × 2 = 4 → (B)
Answer
4
Verify 2112 really is a palindrome: read it backward and you get 2112 — same number. Also check that no palindrome sits between 2002 and 2112. Any palindrome starting with 2 has the form 2BB2, and the only choices for B between 0 and 1 are exactly those two values, giving 2002 and 2112. Nothing in between. Finally, the product 2 × 1 × 1 × 2 = 4 matches choice (B), and the trap answers 0, 9, 16, 25 correspond to mistakenly using 2020, 2332, 2222, or 2552 — none of which is the next palindrome after 2002.
💡Key takeaway

A 4-digit palindrome always reads ABBA, so the next one after 2002 just needs the smallest bump in the middle digit — that gives 2112, and its digits multiply to 4.