Fun Fur for All

If you’ve ever petted a dog, you know how fun and furry they can be. It’s just not as much fun to pat a person on the head. So how many hairs does a dog have? We humans have up to 100,000 hairs on 120-140 square inches of head, or fewer than 1,000 a square inch. But dogs have about 15,000 hairs per square inch. A square foot has 12 x 12 or 144 square inches, so that’s 2,160,000 hairs per square foot…then it just depends how big your dog is!

Wee ones: If you, a dog and an otter are counting hairs, how many of you are hair-counting?

Little kids: If your dog sheds 1,000 hairs a day, how many is that in a week? Count up by thousands!  Bonus: If you brush out your dog every 3 days starting on a Monday, on what days do you brush your pup the next 2 times?

Big kids: If a Dalmatian has your usual 15,000 hairs per square inch, but a Chocolate Lab has twice as many, how many does the lab have?  Bonus: If a whole dog has 1,000 square inches of fur (about 6 square feet) and 15,000 hairs per square inch, how many hairs are on the whole dog?

The sky’s the limit: If a poodle has 15,000 hairs per square inch and a husky has 83,000 per square inch, and your beagle is halfway between, how many hairs does your beagle have?

Answers:
Wee ones: 3 of you.

Little kids: 7,000. You have 1,000, then 2,000, 3,000, 4,000, 5,000, 6,000, 7,000.  Bonus: On Thursday, then on Sunday.

Big kids: 30,000 hairs per square inch.  Bonus: 15,000,000 hairs, which is 15 million!

The sky’s the limit: 49,000 hairs per square inch. Setting aside the thousands, you need the number halfway between 15 and 83. They are 83-15=68 apart, so the halfway mark is 34 more than 15 and 34 less than 83. That gives us 49 either way.

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