Each in the mileage table above represents

Each in the mileage table above represents an entry indicating the distance between a pair of the five cities. If the table were extended to represent the distances between all pairs of 30 cities and each distance were to be represented by only one entry, how many entries would the table then have? 60, 435, 450, 465, 900

2 Explanations

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Maria Segal

Lets solve it for 5*5 chart: we have 25 slots in the table, some of them are empty and some have entries. We can draw a diagonal that divides the table in half - and we see that a less than half the table has entries. Same would be with the 30*30 table: it would contain a bit less than half of 900 entries - a bit less than 450. The only answer that fits this criteria is B.

Jun 20, 2014 • Comment

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Mike McGarry, Magoosh Tutor