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tconnection360
Mar 3, 2013, 11:08 PM
How long would it take to form 2,000 kilometers of ocean crust at a rate of 5 centimeters per year?

Answer
A) 10 million years
B) 20 million years
C) 30 million years
C) 40 million years
I'm not asking for an answer, but I'd appreciate help in solving it. I don't know how to figure it out. Much appreciated! Cheers

Wondergirl
Mar 3, 2013, 11:16 PM
Change kilometers to centimeters, or vice versa, so you have the same unit of measure.

5cm = 0.000050000km

tconnection360
Mar 3, 2013, 11:21 PM
Change kilometers to centimeters, or vice versa, so you have the same unit of measure.

5cm = 0.000050000km

So would it be 10 million years? Do I just divide it or what?

Wondergirl
Mar 3, 2013, 11:23 PM
so would it be 10 million years? do i just divide it or what?
What grade are you in?

tconnection360
Mar 3, 2013, 11:25 PM
What grade are you in?

11th.. please help! I'm really stressing out on this question

Wondergirl
Mar 3, 2013, 11:26 PM
Is this for homeschooling or real school?

Wondergirl
Mar 3, 2013, 11:28 PM
5 cm = 1 year

0.00005 km = 1 year

tconnection360
Mar 3, 2013, 11:28 PM
Is this for homeschooling or real school?

Real school. I really need help in solving this.. please please please. I'd greatly appreciate it!

Wondergirl
Mar 3, 2013, 11:36 PM
Seems like I am doing the entire problem for you.

5 cm = 1 year

0.00005 km = 1 year

Flip the last equation around and plug in each year amount to find out how many kms.

1 year = 0.00005 km.
2 years = ?
10,000,000 years = ?

tconnection360
Mar 3, 2013, 11:45 PM
Seems like I am doing the entire problem for you.

5 cm = 1 year

0.00005 km = 1 year

Flip the last equation around and plug in each year amount to find out how many kms.

1 year = 0.00005 km.
2 years = ?
10,000,000 years = ?

So I multiplied it for 2,000 km and it was .1 so its 10 million years! Correct?

tconnection360
Mar 3, 2013, 11:54 PM
Seems like I am doing the entire problem for you.

5 cm = 1 year

0.00005 km = 1 year

Flip the last equation around and plug in each year amount to find out how many kms.

1 year = 0.00005 km.
2 years = ?
10,000,000 years = ?

Oh wait is it 40 million years?

Wondergirl
Mar 4, 2013, 12:05 AM
10,000,000 years = 10,000,000 x 0.00005 = ?

tconnection360
Mar 4, 2013, 12:08 AM
10,000,000 years = 10,000,000 x 0.00005 = ?

500...

Wondergirl
Mar 4, 2013, 12:14 AM
So 10 Million years would be only 500 km. of ocean crust.

tconnection360
Mar 4, 2013, 12:25 AM
So 10 Million years would be only 500 km. of ocean crust.

Gotcha.. 40! Thanks so much