A bridge is a simple idea: stretch a road from one side of a river to another, and people can cross without having to swim. But this footbridge in Midland, Michigan is a three-way bridge, called the Tridge. The bridge is just 8 feet wide, and each spoke is just 180 feet long from the center to the riverbank, less than 1/20 of a mile. It’s not that far, but definitely easier to walk it than swim.
Lace up: If you drew straight lines to connect the Tridge’s ends to make a 3-sided shape, what shape would that be?
Jog: If you walked on the bridge from the left side, reached the middle and turned right, which part would you then walk on? Point to it.
Sprint: If you lay across the 8-foot-wide Tridge, how much taller would you need to be to stretch across? Find out your height to the closest foot!
Hurdle: Can you add up the 3 180-foot long spokes of the Tridge? What total distance does that make?
High Jump: How long is 1/10 of a mile? (Reminder if needed: A mile has 5,280 feet.)
Pole Vault: If you start on the left, cross the bridge to the upper right corner, then cross from there to the bottom right, then cross again to end up at your start, will 10 full trips like that give you a mile of walking?
Answers:
Lace up: A triangle.
Jog: The bottom right part.
Sprint: Different for everyone…subtract your height in feet from 8.
Hurdle: 480 feet!
High Jump: 528 feet.
Pole Vault: Yes. You walk 6 of these 180-foot spokes in 1 full trip, or 1,080 feet. So 10 trips will require walking 10,800 feet, which is more than the 5,280 feet in a mile – in fact, it’s more than 2 miles!
