Number sense and place value reasoning
About this video
The video uses three clues to find a mystery number from a list of choices. It compares numbers by looking at the ten thousands and thousands places to rule choices out, then uses the digit in the hundreds place to pick the answer.
You'll be able to
- compare 5-digit numbers by looking at their place values from left to right.
- use clues like 'greater than' and 'less than' to rule out numbers.
- find the digit in the hundreds place of a number.
Key words
- greater than
- Bigger than another number; 45,000 is greater than 43,215.
- less than
- Smaller than another number; 45,000 is less than 47,890.
- place value
- The value a digit has because of where it sits in a number, like ones, tens or hundreds.
- hundreds place
- The third place from the right in a whole number; it tells how many hundreds there are.
- rule out
- To decide a choice cannot be the answer, so you cross it off.
Transcript
- [Instructor] We're told: the list below shows three clues about a number. And they say: which of these numbers could be the number described? So why don't you pause this video and try to do this before we do this together? Okay, now let's do this together. So the first clue is the number is greater than 43,215.
So let's see which of these numbers are greater than 43,215. So they all have four 10 thousands, so that doesn't help us much. But if we go to the thousands place, this one only has two thousands. So it's not greater. This is 42,000 and something. So it's definitely less than 43,000 and something.
So we can rule this one out just based on that first clue. Now, these second two, this is 45,000 and something and 46,000 and something. So it's definitely larger than 43,000 and something. So we've used that first clue. We have it down now to two numbers. The second clue: the number is less than 47,890.
Well, both of these... This is 45,000 and something. This is 46,000 and something. So they're both less than 47,000 and something. So this isn't really helping us that much. Now let's look at this last clue. The number has a 6 in the hundreds place. So the hundreds place, this is one, tens, hundreds.
6 in the hundreds place. I like Choice B. Ones, tens, hundreds. This does not have a 6 in the hundreds place. We rule that one out, and B is our answer.
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