### help!

Posted:

**Wed Jan 21, 2015 9:38 pm**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.

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

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Posted: **Wed Jan 21, 2015 9:38 pm**

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.

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

Posted: **Sat Feb 07, 2015 10:23 pm**

can't anyone find the answer i cannot do it so i posted it.

N:B:logic and reason must be given.

N:B:logic and reason must be given.

Posted: **Sat Feb 07, 2015 10:49 pm**

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 $2015$.

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 $2015$.

Posted: **Mon Feb 16, 2015 10:12 pm**

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

Posted: **Tue Feb 20, 2018 11:07 am**

Raiyan Jamil wrote: ↑Mon Feb 16, 2015 10:12 pmThis is the 7th question of junior category Dhaka 2015. The ans is 28098.

Why? the answer is 26600.

Posted: **Tue Feb 20, 2018 2:25 pm**

No,the correct answer is $\fbox {28098}$.Calculate again ,you will get this number.M. M. Fahad Joy wrote: ↑Tue Feb 20, 2018 11:07 amRaiyan Jamil wrote: ↑Mon Feb 16, 2015 10:12 pmThis is the 7th question of junior category Dhaka 2015. The ans is 28098.

Why? the answer is 26600.

Posted: **Tue Feb 20, 2018 4:40 pm**

Eta kivabe calculate korbo? Sutro ta bole diben?samiul_samin wrote: ↑Tue Feb 20, 2018 2:25 pmNo,the correct answer is $\fbox {28098}$.Calculate again ,you will get this number.M. M. Fahad Joy wrote: ↑Tue Feb 20, 2018 11:07 amRaiyan Jamil wrote: ↑Mon Feb 16, 2015 10:12 pmThis is the 7th question of junior category Dhaka 2015. The ans is 28098.

Why? the answer is 26600.

Posted: **Tue Feb 20, 2018 4:48 pm**

If you tell Bangla then use Avro.It is easy.

$(45×20×20)+(45×200)+1000+32+15+45=28098$

$(45×20×20)+(45×200)+1000+32+15+45=28098$

Posted: **Tue Feb 20, 2018 5:32 pm**

বুঝলাম না:

(১) আপনার সূত্র

(২) একবার বলেন 28092 এবং আরেকবার 28098

(১) আপনার সূত্র

(২) একবার বলেন 28092 এবং আরেকবার 28098

Posted: **Tue Feb 20, 2018 5:44 pm**

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