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what is the sum of the digits from 1 to 2015 ?
Ex. sum of the digits from 19 to 21 is: 1+9+2+0+2+1=15.

can't anyone find the answer i cannot do it so i posted it.
N:B:logic and reason must be given.

I am giving you the process of solving it.I hope you will solve it own.
We want to count the sum of the digits of the number $1234567891011.........2015$.See that the sum of the digits from $1$ to $9$ is $45$.Now,the sum of the digits from $10$ to $19$ is $10\times1+45=55$.In this process you can count the total sum.
$\text{Another way}:$
Find the number of $1's$,number of $2's$...........number of $9's$ from $1$ to $2015$.

This is the 7th question of junior category Dhaka 2015. The ans is 28098.

Raiyan Jamil wrote: ↑

Mon Feb 16, 2015 10:12 pm

This is the 7th question of junior category Dhaka 2015. The ans is 28098.

Why? the answer is 26600.

M. M. Fahad Joy wrote: ↑

Tue Feb 20, 2018 11:07 am

Raiyan Jamil wrote: ↑

Mon Feb 16, 2015 10:12 pm

This is the 7th question of junior category Dhaka 2015. The ans is 28098.

Why? the answer is 26600.

No,the correct answer is $\fbox {28098}$.Calculate again ,you will get this number.

samiul_samin wrote: ↑

Tue Feb 20, 2018 2:25 pm

M. M. Fahad Joy wrote: ↑

Tue Feb 20, 2018 11:07 am

Raiyan Jamil wrote: ↑

Mon Feb 16, 2015 10:12 pm

This is the 7th question of junior category Dhaka 2015. The ans is 28098.

Why? the answer is 26600.

No,the correct answer is $\fbox {28098}$.Calculate again ,you will get this number.

Eta kivabe calculate korbo? Sutro ta bole diben?

If you tell Bangla then use Avro.It is easy.
$(45×20×20)+(45×200)+1000+32+15+45=28098$

বুঝলাম না:
(১) আপনার সূত্র
(২) একবার বলেন 28092 এবং আরেকবার 28098

The main object of this forum is to make our students interested in maths. So we should not be bothered but helping each other.