Best Guess · Puzzle #33 · Sunday, November 1
Best Guess: the answers
Four questions, each with one true number. Here they are with their answers, how to reason each one out, and where the number comes from. Play today's Best Guess.
1. How many vehicles cross San Francisco's Golden Gate Bridge on a typical day?
The answer: about 112,000. The bridge is a fixed six-lane roadway 1.7 miles long.
Napkin math - 6lanes on the bridge
- ×1,000cars a lane each hour
- ×18hours of steady traffic a day
≈108kvehicles
The true figure is about 112,000 vehicles (Golden Gate Bridge, Highway and Transportation District). To reason it out, take 6 lanes on the bridge, times 1,000 cars a lane each hour, times 18 hours of steady traffic a day, and you get about 110,000 vehicles. That is almost exactly the real number, and a guess like it scores 9.8 out of 10. Any guess from 56,000 vehicles to 220,000 vehicles scores 7.0 or better, because the game only counts how many times off you are.
Source: Golden Gate Bridge, Highway and Transportation District, Bridge Operations
2. How many people (associates) work for Walmart worldwide?
The answer: about 2.1 million. About 1.6 million of them work in the US and about 0.5 million in other countries.
Napkin math - 5,000Walmart stores in the US
- ×300workers a store
≈1.5Massociates
The answer comes to about 2.1 million associates (Walmart Inc.). On a napkin, take 5,000 Walmart stores in the US, times 300 workers a store, and you get about 1.5 million associates. The estimate is 1.4 times too low, close enough to score 8.5 out of 10. The target is wider than it looks: every guess between 1.1 million associates and 4.2 million associates scores at least 7.0.
Source: Walmart Inc., Form 10-K for fiscal year ended January 31, 2026
3. Central Park covers 843 acres. How many trees grow there?
The answer: about 18,000. Those trees cool Manhattan in summer, when the island becomes an urban heat island.
Napkin math - 843acres of park
- ×20trees an acre
≈16.9ktrees
The real answer is about 18,000 trees (Central Park Conservancy). To reason it out, take 843 acres of park, times 20 trees an acre, and you get about 17,000 trees. That comes out 1.1 times too low, and a guess that far off still scores 9.7 out of 10. Because only the ratio counts, anything between 9,000 trees and 36,000 trees was worth 7.0 or more.
Source: Central Park Conservancy, A Need for Trees: How Central Park Cools the Heat Island
4. How many boys played 11-player high school football in the US in 2024-25?
The answer: about 1.03 million. Football is the most-played boys' high school sport, ahead of outdoor track and field.
Napkin math - 20khigh schools in the US
- ×50players on a school's football program
≈1Mplayers
The true figure is about 1.03 million players (National Federation of State High School Associations). On a napkin, take 20,000 high schools in the US, times 50 players on a school's football program, and you get about 1 million players. That lands all but on the answer, worth 9.9 out of 10 as a guess. Because only the ratio counts, anything between 510,000 players and 2.1 million players was worth 7.0 or more.