Sightseeing
by Nathan Fung
ANSWER: KEY WITNESS
Each red dot on the map indicates a location where a red balloon was moored in the DARPA challenge. In their original order:
| Balloon | Location | Road arithmetic |
|---|---|---|
| 10 | Centennial Park, Atlanta, Georgia | 20 - 1 = 19 (S) |
| 7 | Glasgow Park, Christiana, Delaware | 40 - 26 = 14 (N) |
| 5 | Lee Park, Memphis, Tennessee | 40 - 31 = 9 (I) |
| 1 | Union Square, San Francisco, California | 80 - 69 = 11 (K) |
| 9 | Waterfront Park, Portland, Oregon | 84 - 65 = 19 (S) |
| 8 | Katy Park, Katy, Texas | 99 - 94 = 5 (E) |
| 2 | Chaparral Park, Scottsdale, Arizona | 101 - 96 = 5 (E) |
| 4 | Chase Palm Park, Santa Barbara, California | 225 - 202 = 23 (W) |
| 3 | Tonsler Park, Charlottesville, Virginia | 631 - 606 = 25 (Y) |
| 6 | Collins Avenue, Miami, Florida | 922 - 902 = 20 (T) |
Ordering the locations by balloon number and performing the subtraction on each road number, the numbers spell the answer KEY WITNESS alphanumerically.