Track / Stage 4 / 48 of 340 #308 of 1964

2. Which two weights need to be swapped to balance the scale? (The unit of all weights is grams)

Pick one

A 1 and 4 B 9 and 2 C 9 and 4 D 7 and 3 E 7 and 4

Show the answer

Official solution

D

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Source: NuminaMath-1.5, licensed Apache-2.0. Statement and solution reproduced as published; topic, difficulty and ordering added by this site.