CEMC Fermat, 2013

Combinatorics Difficulty 1.1 Junior Find the answer Canada

A large cylinder can hold 50 L of chocolate milk when full.

The tick marks show the division of the cylinder into four parts of equal volume. Which of the following is the best estimate for the volume of chocolate milk in the cylinder as shown?

Pick one

Solution

Since the tick marks divide the cylinder into four parts of equal volume, then the level of the milk shown is a bit less than $\frac{3}{4}$ of the total volume of the cylinder.

Three-quarters of the total volume of the cylinder is $\frac{3}{4}\times 50 = 37.5$ L.

Of the five given choices, the one that is slightly less than 37.5 L is 36 L, or (D).

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