AMC 2021 Middle Primary – Problem 14 with Solution | Australian Mathematics Competition Explained
Join Trial or Access Free ResourcesJoin Trial or Access Free ResourcesLet's discuss a problem from the AMC 2021 Middle Primary Category: Problem 14 which revolves around basic algebra.
Five boxes are compared on a balance.
Which of the five boxes is lightest?
From the picture we can understand that box $C$ isd lighter than box $A$. Again box $C$ is heavier than box $D$. Thus box $C$ is not lightest.
Box $D$ is lighter than box $C$ but heavier than box $E$. So box $D$ is not lightest.
Box $E$ is lighter than box $D$ but heavier than box $B$.
Thus the relation we get is:
$A\li C \li D \li E \li B$.
Thus box $B$ is the lightest.
The Australian Mathematics Competition (AMC) is one of Australia's largest and oldest annual mathematics competitions, aimed at fostering interest and excellence in mathematics among students.
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