Digits 5

harpazo

harpazo

Full Member
Joined
Jan 31, 2013
Messages
891
The sum of the digits of a 2-digit number is 13. If 18 is added to the number, the result is the number with its digits reversed. Find the original number.

Solution:

Let a = tens digit
Let b = ones digit

a + b = 13
18+ 10a + b = 10b + a

Is this the correct set up?
 
harpazo said:
The sum of the digits of a 2-digit number is 13. If 18 is added to the number, the result is the number with its digits reversed. Find the original number.

Solution:

Let a = tens digit
Let b = ones digit

a + b = 13
18+ 10a + b = 10b + a

Is this the correct set up?
Click to expand...

no...

10a+b =13, oh.. you seem to have realized your mistake in the 2nd line.

10a+b+18 = 10b+a

is the correct equation.
 
Romsek said:
no...

10a+b =13, oh.. you seem to have realized your mistake in the 2nd line.

10a+b+18 = 10b+a

is the correct equation.
Click to expand...

I corrected my mistake. This is what I care about more than anything else in math---setting up equations. My inability to do this has kept me away from a healthy check in my hometown as a math tutor.
 
harpazo said:
The sum of the digits of a 2-digit number is 13. If 18 is added to the number, the result is the number with its digits reversed. Find the original number.

Solution:

Let a = tens digit
Let b = ones digit

a + b = 13
18+ 10a + b = 10b + a

Is this the correct set up?
Click to expand...
Am I missing something? There seems to be no solution to this.
49 + 18 is not 94
58 + 18 is not 85
67 + 18 is not 76
76 + 18 is surely not 67
...
 
Jomo said:
Am I missing something? There seems to be no solution to this.
49 + 18 is not 94
58 + 18 is not 85
67 + 18 is not 76
76 + 18 is surely not 67
...
Click to expand...

it's them special digits \(\displaystyle Q=\dfrac{11}{2}, S=\dfrac{15}{2}\)
 
HallsofIvy said:
A "healthy check" as a math tutor? What town is this?
Click to expand...

In NYC, most tutors are paid 20 dollars per hour which is 5 dollars more than the minimum wage in our state. However, work is mainly part-time with Kumon, Princeton, Sylvan, Kaplan and the rest of the tutoring companies. Tutoring a great second income. Extra money in NYC helps, every little bit helps.
 
Jomo said:
Am I missing something? There seems to be no solution to this.
49 + 18 is not 94
58 + 18 is not 85
67 + 18 is not 76
76 + 18 is surely not 67
...
Click to expand...

I went back to the website. The problem is given as I posted here. It is also given as the following:

The sum of the digits of a 2-digit number is 14. If 18 is added to the number, the result is the number with its digits reversed. Find the original number.
 
harpazo said:
In NYC, most tutors are paid 20 dollars per hour which is 5 dollars more than the minimum wage in our state.
Click to expand...
I really do wonder if you make this stuff up. NYC is an extremely expensive area so why do you think that tutoring would be so cheap? SAT tutors earn $100 minimum per hour. This is a fact which I will not debate with you. In 1986 while I was an undergraduate student I was charging $20 per hour for college tutoring. You want me to believe that 34 years later the fee has not gone up. I was born at night but not last night.
 
Romsek said:
it's them special digits \(\displaystyle Q=\dfrac{11}{2}, S=\dfrac{15}{2}\)
Click to expand...

The problem is also given this way:

The sum of the digits of a 2-digit number is 14. If 18 is added to the number, the result is the number with its digits reversed. Find the original number.

The sum equated to 14 instead of 13.
 
Jomo said:
I really do wonder if you make this stuff up. NYC is an extremely expensive area so why do you think that tutoring would be so cheap? SAT tutors earn $100 minimum per hour. This is a fact which I will not debate with you. In 1986 while I was an undergraduate student I was charging $20 per hour for college tutoring. You want me to believe that 34 years later the fee has not gone up. I was born at night but not last night.
Click to expand...

1. I hate the fact that you call me a liar in ALMOST every single reply.

2. This is disrespectful, RUDE, AND CHILDISH.

3. Stop replying to my post. I have told you this about 100 million times.

4. I have no reason to lie about this or anything else. I am a Christian. You are insulting my faith in the Lord Jesus Christ.

5. PLEASE, PLACE ME ON YOUR IGNORE LIST. If I could block you, I would.

BY THE WAY, I DID NOT MAKE ANYTHING UP. CHECK OUT THE WEBSITES FOR THE COMPANIES LISTED AND LEAVE ME ALONE. I AM GOING TO CONTACT TED ABOUT YOU NOW.
 
I speak the truth. In NYC math tutoring is at $75 per hour if you have any talent.
 
harpazo said:
1. I hate the fact that you call me a liar in ALMOST every single reply.

2. This is disrespectful, RUDE, AND CHILDISH.

3. Stop replying to my post. I have told you this about 100 million times.

4. I have no reason to lie about this or anything else. I am a Christian. You are insulting my faith in the Lord Jesus Christ.

5. PLEASE, PLACE ME ON YOUR IGNORE LIST. If I could block you, I would.

BY THE WAY, I DID NOT MAKE ANYTHING UP. CHECK OUT THE WEBSITES FOR THE COMPANIES LISTED AND LEAVE ME ALONE. I AM GOING TO CONTACT TED ABOUT YOU NOW.
Click to expand...

As far as I know, you should be able to ignore anyone who is not a staff member. There is no need to contact Ted over this. This is what moderating staff is for. Jomo is not breaking any forum rules, and so it is up to you to either put him on ignore, or just ignore any replies you don't like the old fashioned way. You cannot tell others to ignore you...that is up to the individual who they choose to ignore, or not.
 
Jomo said:
I speak the truth. In NYC math tutoring is at $75 per hour if you have any talent.
Click to expand...

I do not get it. You can solve math problems but do not understand IGNORE MY THREADS, REPLIES, IGNORE ME. AM I TALKING TOPOLOGY HERE? I am not interested in anything else you have to say, sir.
 
MarkFL said:
As far as I know, you should be able to ignore anyone who is not a staff member. There is no need to contact Ted over this. This is what moderating staff is for. Jomo is not breaking any forum rules, and so it is up to you to either put him on ignore, or just ignore any replies you don't like the old fashioned way. You cannot tell others to ignore you...that is up to the individual who they choose to ignore, or not.
Click to expand...

Will do. Thanks, Mark.
 
MarkFL said:
As far as I know, you should be able to ignore anyone who is not a staff member. There is no need to contact Ted over this. This is what moderating staff is for. Jomo is not breaking any forum rules, and so it is up to you to either put him on ignore, or just ignore any replies you don't like the old fashioned way. You cannot tell others to ignore you...that is up to the individual who they choose to ignore, or not.
Click to expand...

He is now on my ignore list.
 
harpazo said:
I went back to the website. The problem is given as I posted here. It is also given as the following:

The sum of the digits of a 2-digit number is 14. If 18 is added to the number, the result is the number with its digits reversed. Find the original number.
Click to expand...
Are you saying that it is given twice, once with 13 ("as I posted here"), and again with 14? Or did you just miscopy? Clearly, only the version with 14 is valid. If they did post it with 13, I wouldn't go back there!
 
Dr.Peterson said:
Are you saying that it is given twice, once with 13 ("as I posted here"), and again with 14? Or did you just miscopy? Clearly, only the version with 14 is valid. If they did post it with 13, I wouldn't go back there!
Click to expand...

Good idea. Not going back to that website.
 
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