## help!

For students upto class 5 (age upto 12)
ahsaf
Posts: 16
Joined: Mon Jan 19, 2015 10:48 pm
Location: dhaka, bangladesh

### help!

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.

ahsaf
Posts: 16
Joined: Mon Jan 19, 2015 10:48 pm
Location: dhaka, bangladesh

### Re: help!

can't anyone find the answer i cannot do it so i posted it.
N:B:logic and reason must be given.
Men are born with the reason to help others.
But I realised they strive to become famous.

tanmoy
Posts: 288
Joined: Fri Oct 18, 2013 11:56 pm
Location: Rangpur,Bangladesh

### Re: help!

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 $2015$.
"Questions we can't answer are far better than answers we can't question"

Raiyan Jamil
Posts: 138
Joined: Fri Mar 29, 2013 3:49 pm

### Re: help!

This is the 7th question of junior category Dhaka 2015. The ans is 28098.
A smile is the best way to get through a tough situation, even if it's a fake smile.

M. M. Fahad Joy
Posts: 120
Joined: Sun Jan 28, 2018 11:43 pm
Location: Bhulta, Rupganj, Narayanganj
Contact:

### Re: help!

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.
Math is the main inspiration of my life.

samiul_samin
Posts: 999
Joined: Sat Dec 09, 2017 1:32 pm

### Re: help!

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.

M. M. Fahad Joy
Posts: 120
Joined: Sun Jan 28, 2018 11:43 pm
Location: Bhulta, Rupganj, Narayanganj
Contact:

### Re: help!

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?
Math is the main inspiration of my life.

samiul_samin
Posts: 999
Joined: Sat Dec 09, 2017 1:32 pm

### Re: help!

If you tell Bangla then use Avro.It is easy.
$(45×20×20)+(45×200)+1000+32+15+45=28098$
Last edited by samiul_samin on Tue Feb 20, 2018 6:34 pm, edited 1 time in total.

M. M. Fahad Joy
Posts: 120
Joined: Sun Jan 28, 2018 11:43 pm
Location: Bhulta, Rupganj, Narayanganj
Contact:

### Re: help!

বুঝলাম না:
(১) আপনার সূত্র
(২) একবার বলেন 28092 এবং আরেকবার 28098
Math is the main inspiration of my life.

M. M. Fahad Joy
Posts: 120
Joined: Sun Jan 28, 2018 11:43 pm
Location: Bhulta, Rupganj, Narayanganj
Contact:

### Re: help!

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