Video Transcript
Finding One, 10, 100, 1,000, or
10,000 More or Less
In this video, we’re going to learn
how to use place value to add or subtract one, 10, 100, 1,000, or 10,000 from a
given number and how to complete number patterns. In this video, we’re going to work
with numbers with four or five digits.
Let’s take a minute to think about
the place value of each of these digits. This is the ones digit. The smallest one-digit number we
can make is number one, and the largest one-digit number we can have is number
nine. If we add one more to the number
nine, we’ll have 10. This is the smallest two-digit
number we can make. The greatest two-digit number we
can make is the number 99. And if we add one more, we need to
move into the hundreds column. The smallest three-digit number we
can make is 100, and the greatest three-digit number is 999. If we add one more to 999, we have
to move into the thousands column. 1,000 is the smallest four-digit
number we can make. The greatest four-digit number we
can make is 9,999. And if we add one more, we’ll have
10,000, which is the smallest five-digit number we can make. And the largest is 99,999.
The position of each digit tells us
its place value. For example, the three digit in the
number 95,364 is worth 300. The three is in the hundreds
place. But if we change the order of the
digits around, the three digit in the number 35,964 is worth 30,000. The three digit is in the ten
thousands place.
Let’s see what happens if we add
one to this number. The digit in the ones place is a
four, worth four ones. So if we add one more, we’ll have
five ones. The ones digit has increased by
one. If we were to subtract one from the
number 35,964, instead of having four ones, we’d have three. The ones digit has decreased by
one. And if we were to subtract 1,000
from the number 35,964, the number of thousands would also decrease by one. We had five 1,000s. Now we have four.
Sometimes more than one digit in
the number changes. Watch what happens if we add 100 to
our number. Now we have 10 hundreds, and we
need to regroup. By adding 1,000 into the thousands
place, two of our digits have changed, the hundreds digit and the thousands
digit. So when we’re adding one, 10, 100,
1,000, or 10,000, sometimes we have to regroup, and more than one digit changes.
How many digits do you think will
change if we add one to the number 39,999? All of the digits would change. 39,999 plus one is 40,000. Let’s have a go at answering some
questions now, and we can put into practice what we’ve learned about place
value.
Find 10,000 more than the number
given in the table.
In this question, we’ve been given
a five-digit number in a place value table. And we have to find 10,000 more
than this number. This number has 62 1,000s. Our number is 62,100. This is the ten thousands
digit. The six is worth six 10,000s. 10,000, 20,000, 30,000, 40,000,
50,000, 60,000. If we add one more 10,000, instead
of having six 10,000s, we’ll have seven, and the seven digit will be worth
70,000. 10,000 more than 62,100 is
72,100. The ten thousands digit increased
by one.
Complete the following table.
In this question, we’re given a
four-digit number, 5,666. In this column, we have to write
the answer to 5,666 take away one. In the next column, we have to
subtract 10 from 5,666 and write the answer here. Next, we need to subtract 100 from
our number and write the answer here. And in the last column, we need to
subtract 1,000 from our number and write the answer here.
Writing the number in a place value
table helps us to understand the value of each digit. The number 5,666 has five 1,000s,
six 100s, six 10s, and six ones. What is 5,666 take away one? We already know our number has six
ones. If we take one away, we’ll have
five ones left. 5,666 take away one is 5,665. The ones digit has decreased by
one.
Now we need to take away 10 from
our number. The tens digit is also a six, and
this is worth 60. If we take away one 10, we’ll have
five 10s. The tens digit has decreased by
one.
Now we have to take away 100 from
our number. The digit in the hundreds place is
also a six. If we have six 100s and we take one
away, we have five 100s left. 5,666 take away 100 is 5,566. The hundreds digit has decreased by
one.
Finally, we need to subtract 1,000
from our number. The digit in the thousands place is
a five. And if we take one 1,000 away,
we’ll have four 1,000s left. 5,666 take away 1,000 is 4,666. This time, the thousands digit
decreased by one.
We completed the table by taking
away one, 10, 100, and 1,000 from the number 5,666. The missing numbers are 5,665,
5,656, 5,566, and 4,666. We used our knowledge of place
value to help us subtract.
Find the missing numbers in the
following pattern: 96,000, what, 76,000, what, 56,000.
In this question, we’re given a
number pattern and we have to find the two missing numbers. We can tell from the three numbers
we are given that this is a decreasing number pattern: 96,000, 76,000, 56,000. The thousands part of the number is
decreasing. What’s the difference between
96,000 and 76,000? The nine digit in 96,000 has
decreased by two, to a seven in the number 76,000. The difference between 96,000 and
76,000 is 20,000, and the difference between 76,000 and 56,000 is also 20,000.
The digit in the ten thousands
place is decreasing by two: 96,000, 76,000, 56,000. So if the difference between our
given numbers is 20,000, the midway point between each pair of numbers must be half
that amount. We know that half of 20 is 10, so
half of 20,000 is 10,000. So 10,000 less than 96,000 is
86,000; 10,000 less than 86,000 is 76,000; and 10,000 less than 76,000 is
66,000. And we know that 10,000 less than
66,000 is 56,000. Our numbers are decreasing by
10,000 each time: 96,000, 86,000, 76,000, 66,000, and 56,000. The missing numbers in the pattern
are 86,000 and 66,000. The rule of the pattern is to
subtract 10,000 each time.
What have we learned in this
video? We have learned how to find one,
10, 100, 1,000, or 10,000 more or less than a number using our knowledge of place
value.
