That’s One Heavy Ocean

Our friend Parker M. asked, how much does the ocean weigh? Well, a box of water 1 foot wide, 1 foot long and 1 foot tall would weigh 62 1/2 pounds! Scientists guess that there are 326 million cubic miles of water, meaning boxes a whole mile wide, a mile long and a mile tall. Each box edge is 5,280 feet long, so there are 5,280 x 5,280 x 5,280 little 1-foot boxes in each cubic mile…we get 47,986,532,352,000,000,000 boxes, or almost 48 *quintillion*. They would weigh about 3 sextillion pounds. We’re glad we don’t have to weigh it cup by cup!

Wee ones: Plug a sink, turn on the water while you count to 5, then turn it off. Is the sink a little bit full, half full, or totally full?

Little kids: If you drink a cup of water at breakfast, then lunch, then dinner, plus 3 more cups in the afternoon, how many cups do you drink each day?  Bonus: How many more would you need to drink a half-gallon (8 cups)?

Big kids: 1 gallon of water weighs about 8 pounds. How many gallons of water match your weight? (Hint if needed: 8 is 2 x 2 x 2, so to divide by 8, you just cut in half 3 times in a row.)  Bonus:How much does a 40-gallon bathtub of water weigh, if each gallon weighs about 60 pounds?

Wee ones: It should probably be only a little bit full.

Little kids: 6 cups.  Bonus: 2 more cups.

Big kids: Different for everyone…divide your weight by 8, or see how many 8s you need to add up to match your weight.  Bonus: 2,400 pounds!

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