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Google·Product Manager·Onsite - Product Sense / Strategy·Intermediate

Intermediate
Jun 2026

Summary

PM interview at Google with a classic estimation question about bike-sharing in NYC. Pretty standard product sense round, nothing too surprising.

Questions Asked (1)

Q1

How many bikes would you need to launch a bike-sharing service in New York City?

Product Sense & IdeationProduct Analytics & MetricsProduct Strategy
Author's notes

I started with population and geographic density, broke NYC into boroughs, then tried to estimate daily trips per bike.

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AI HintsAI Generated

Suggested Approach

Start by clarifying the goal and constraints of the bike-sharing service, then estimate demand based on population and usage patterns, and finally calculate the required fleet size considering operational factors like rebalancing and maintenance. Use a structured, top-down approach with clear assumptions and sanity checks.

Pro tip: Show that you understand the difference between a launch fleet and a steady-state fleet, and emphasize that the initial number should be a pilot to validate demand and operations before scaling.

1. Clarify Scope and Assumptions

Ask clarifying questions to define the service area, target users, and launch goals (e.g., pilot vs. full-scale). Establish key assumptions like population, bike availability, and usage frequency.

2. Estimate Demand

Calculate potential daily trips by segmenting the population (e.g., residents, commuters, tourists) and estimating adoption rates and trips per user per day. Use benchmarks from other bike-sharing systems.

3. Determine Fleet Size from Demand

Convert daily trips to required bikes using average trips per bike per day, which depends on ride duration, operating hours, and turnover. Account for peak demand and bike availability.

4. Adjust for Operational Factors

Add buffers for maintenance, rebalancing, and downtime. Consider the need for spare bikes and the impact of docking station capacity.

5. Sanity Check and Recommend

Validate the number against benchmarks (e.g., bikes per capita in other cities) and propose a phased rollout starting with a pilot. Summarize the final estimate with key assumptions.

Key Points to Mention

  • Population and target market segmentation (e.g., residents, commuters, tourists)
  • Adoption rate and usage frequency benchmarks from existing bike-sharing systems
  • Average trips per bike per day and the impact of ride duration and operating hours
  • Operational buffers for maintenance, rebalancing, and peak demand
  • Phased launch approach to validate demand and operations
  • Sanity checks using bikes per capita or similar metrics

AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.