Question

A Brachiosaurus weighing 60,000 lbs has a brain that weighs 0.15 lbs. If your brain was the same ratio as this dinosaur, how much would it weigh? What object would be about the same size of your brain?

Answer 1

Are you given the weight of the human?

Answer 2

Yes, sorry. 100 lbs.

Answer 3

ok, so if your given ratio is .15lbs:60Klbs, you have to set it equal to another, uncompleted, ratio: "x:100"

Answer 4

it can also be stated as "

Answer 5

so, you can cross multiply at this point. Do you know how?

Answer 6

I'm not sure. When I did it, I got 15 and I know that can't be right. It has to be a number with a lot of zeros in front of it.

Answer 7

ok, to cross multiply, you have to solve "100 x .15= 60000 x (x, the number to be found)"

Answer 8

Can you do that?

Answer 9

I'm not getting it right.

Answer 10

that's fine, just show me how you're solving it.

Answer 11

That time I got 9000. I multiplied .15 by 100, then tried .15 by 60000.

Answer 12

why'd you multiply .15 times 60000?

Answer 13

Because I'm grabbing at straws???

Answer 14

hehe, well don't worry, you did some of it right.

Answer 15

what did you get when you multiplied .15 x100?

Answer 16

15

Answer 17

ok, so, on the other side we're left with 60000 x (number to be found). SO, what's the opposite of multiplication?

Answer 18

Division...15 divided by 60000 = .00025????

Answer 19

yep.

Answer 20

So, if our brains were sized with the same ratio, the human brain would weigh 250 micro pounds.

Answer 21

As to the object, that's up to you.

Answer 22

Wow...thank you!!!

Answer 23

welcome!