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A foghorn is a device that uses sound to warn vehicles of hazards in foggy conditions. Many lighthouses have foghorns that blast at periodic intervals. Watch the video to learn about foghorns.

  1. The Beavertail Lighthouse in Rhode Island blasts its foghorn once every 30 seconds.

    • What is the rate expressed in blasts per minute?
    • How many times will the foghorn blast in 1 hour?
  2. Before electronic foghorns were invented, the lighthouse keeper periodically fired a cannon. If the lighthouse keeper fired the cannon 20 times per hour, what is the rate in blasts per minute?

  3. Foghorns are checked after 10,000 blasts.

    • How often is the Beavertail Lighthouse foghorn checked?
    • If the cannon was also checked at the same rate, how often would that be?
  4. Research the foghorns at the Golden Gate Bridge in San Francisco. The foghorns are located in two locations: at the middle of the bridge (midspan) and at the south (San Francisco) tower pier. The foghorns have different sounds. Create a problem about their rates.

VIDEO: Foghorns