00:01
Here's some data about mobile messaging versus total instant messaging.
00:07
And this was back in 2006 to 2010, so when mobile messaging wasn't that popular yet.
00:14
So they give us crucial information.
00:16
T equals zero corresponds to 2006.
00:19
T equals four corresponds to 2010.
00:21
And they ask us some questions about 2008, which means they're asking about t equals two.
00:28
Okay, so first they ask us what percentage of mobile accounts, what percentage of im accounts were mobile in 2008, so we're just looking for p of 2.
00:45
And so we can just go ahead and substitute 2 in 4t.
00:50
We're multiplying by 2 squared, which is 4 plus 0 .57 times 2 plus 3 .9.
00:58
And then there's a bunch of decimals, so we'll just go ahead and put that into a calculator.
01:05
257 times 4.
01:06
Make sure if there's any parentheses, there may not have to be, in this case, if you have a nice enough calculator, that does order of operations for you.
01:15
And then we don't even have to round...