Estimating to the nearest tens by rounding off
Once Ayush asked his friend Mohan to give him
$28$
rupees to pay for a book.
Mohan gave him
$30$
rupees.
Ayush then told him that he only needed
$28$
rupees.
Mohan said that
$30$
rupees is approximately equal to
$28$
rupees.
Ayush got confused so, Mohan explained him about estimation to the nearest tens by rounding off.
Letâ€™s discuss the estimation of numbers to the nearest tens by rounding off.
Letâ€™s consider a group of numbers from
$0$
to
$10$
as
Here we can observe that number
$1$
to
$4$
are closer to
$0$
in comparison with
$10$
.
And, the numbers
$5$
to
$9$
are closer to
$10$
in comparison with
$0$
.
In case of estimating to nearest tens, we always look at the tens value which are nearest to the number.
We follow same concept for finding out estimated values nearest to tens.
Let us consider a
$2$
digit number
$28$
and we need to estimate this to the nearest tens
Here, we observe that it is nearer to
$30$
so, it is rounded off to
$30$
.
Now, suppose we consider a
$2$
digit number
$89$
and we need to estimate this number to the nearest tens by rounding off.
We can clearly observe that
$89$
is nearest to
$90$
. So, its estimated value will be
$90$
We see some other examples and round off them to their closer number as
Revision
Number
$1$
to
$4$
are closer to
$0$
in comparison with
$10$
so, it is rounded off to
$0$
.
Number
$5$
to
$9$
are closer to
$10$
in comparison with
$0$
so, it is rounded off to
$10$
.
In case of estimating to nearest tens we always look at the tens value which are nearest to the number.
Suppose we to have to estimate it to its nearest tens.
As it is nearest to
$40$
,so its estimated value will be
$40$
.
The End