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Are Fish Invisible?

by Derek Stump

Well, no – but they might as well be. Scientists just realized there are at least 10 times more fish in the ocean than we thought. The fish are hanging out in the “twilight zone” of the ocean, 500 – 3,200 feet below the waves. They come closer to the surface to eat, but they do it at night. So scientists used sonar – sending a sound through the water, and seeing if it bounces off fish – to estimate how many fish there were. That’s when they started uncovering some very fishy numbers!


Wee ones: If you’re counting fish and have counted up to 6, what number do you say next?

Little kids: If you’re searching for fish and spot 1 fish every 2 minutes, how long will it take you to spot 5 fish? Bonus: If you expected to find 5 fish and found 10 times more than that, how many fish did you find?


Big kids: If a sonar “ping” travels 200 feet from the ocean surface to the floor, bounces off the floor and comes straight back up to the surface, how many feet does it travel? Bonus: If there are 95 hidden fish for every 5 fish you see, and you see 15 fish, how many hidden fish must there be?

Answers:

Wee ones: 7.


Little kids: 10 minutes. Bonus: 50 fish.

Big kids: 400 feet: 200 down + 200 up. Bonus: 285 hidden fish. 15 visible fish means there are 3 sets of 95 hidden fish, because 15 / 5 = 3.

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