Using the subway system shown below, Mr. P needs to travel from his home in the lower left corner of the map to his office (near the upper right).
Normally, he would ride four stops east on the green line, change at station H, and ride three stops north on the blue line.
But today, the metro is having an economy drive to save fuel and encourage everyone to exercise more. All trains only stop at every third station. (However, different trains on a line may begin at different stations so that all stations are eventually served; e.g., some red line trains stop at A-J-I, others D-M-L, etc. Thus, you can always change lines at any station.).So, from home on the green line, Mr. P can only ride to station J or station N. The ticket office suggests that he ride to station N, change to the yellow line, ride 3 stops to station B, and then walk the last mile to the office.
But Mr. P is sure that he can beat the system and go the whole way by Metro. What is his route?
Solution to the Problem:
One route is:
Home - J - A - R - L - M - F - C - O - P - H - Office.
Liz Cotter sent in a different solution:
the Green train to J (3 stops), Then
the Red train to I (3 stops), then
the Yellow train to D (3 stops), then
the Red train to M (3 stops), Then
the Blue train to F (3 stops), Then
the Yellow train to C (3 stops), then
the Orange train to P (6 stops), Then
the Green train to H (3 stops), Then
the Blue train to the office.
James Alarie and Les Walker sent in yet another solution:
From home, take the green line to station N.
From N take yellow to B.
From B take the blue to F, then yellow to C, then orange to P, then green to H or Q (your choice). From H or Q take blue to your office.
Correctly solved by:
| 1. Liz Cotter | Austin, Texas |
| 2. James Alarie | Flint, Michigan |
| 3. Les Walker | Ventura. California |