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CAHSEE Math 2.3 Mathematical Reasoning 181 Views
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Description:
CAHSEE Math: Mathematical Reasoning Drill 2, Problem 3. Where else on the number line can X be located and still satisfy the above condition?
Transcript
- 00:03
Here’s some numbers; shmoop us maybe…
- 00:09
On a number line, the point X is twice as far from B as it is from A, as shown below.
- 00:13
Where else on the number line can X be located and still satisfy the above condition?
- 00:18
Here are the potential answers…
- 00:25
Okay, we’ve got another logic problem here.
Full Transcript
- 00:27
No advanced mathematics required, so you can put away the graphing calculator.
- 00:32
Let’s reason through what the problem is actually asking us.
- 00:35
We have point X, and we can see by looking at the number line that it’s at “3.”
- 00:40
A is located at “2” here and B is located at “5” here.
- 00:44
Sure enough, there are twice as many spots between X and B as between X and A.
- 00:49
Now… we could come up with a formula to figure this thing out… using absolute value…
- 00:53
…but our time is precious, and we should be able to test each of our answer choices
- 00:57
quickly and see which one works.
- 01:01
If X was at -2, there would be 4 spots between
- 01:04
X and A… 7 spots between X and B. Not quite double.
- 01:08
If X was at -1, there would be 3 spots between X and A… 6 spots between X and B.
- 01:14
Boom goes the dynamite. 6 is twice as much as 3…
- 01:17
…so our answer is B.
- 01:19
As in, “Bellyache.”
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