SOLUTION: The sum of the digits of a two-digit counting number was 11. When the digits were reversed, the new number was 10 more than one-half the original number. What was the original nu

Algebra.Com
Question 82606: The sum of the digits of a two-digit counting number was 11. When the digits were reversed, the new number was 10 more than one-half the original number. What was the original number?
Answer by ankor@dixie-net.com(22740)   (Show Source): You can put this solution on YOUR website!
Let x = the 10's digit; let y = the units digit
:
"The sum of the digits of a two-digit counting number was 11."
x + y = 11
or x = (11 - y)
:
"When the digits were reversed, the new number was 10 more than one-half the original number."
10y + x = .5(10x + y) + 10
:
What was the original number?
:
10y + x = .5(10x + y) + 10
10y + x = 5x + .5y + 10
10y -.5y = 5x - x + 10
9.5y = 4x + 10
replace x with (11-y)
9.5y = 4(11-y) + 10
9.5y = 44 - 4y + 10
9.5y + 4y = 54
13.5y = 54
y = 54/13.5
y = 4
:
find x:
x = 11-y
x = 11-4
x = 7
:
The number: 74
:
:
Check using:
"When the digits were reversed, the new number was 10 more than one-half the original number."
47 = .5(74) + 10
47 = 37 + 10

RELATED QUESTIONS

The sum of the digits of a two-digit counting number was 9. When the digits were... (answered by Nate,ankor@dixie-net.com)
The sum of the digits of a two digit counting number is 15 , when the digits are reversed (answered by ikleyn,Alan3354)
The sum of the digits of a two-digit number is 11. if the digits are reversed, the new... (answered by Stitch)
2) The sum of the digits of a two- digit counting number is 6. When the digits are... (answered by ikleyn,josgarithmetic,greenestamps)
When the digits of a two-digit number are reversed, the new number is 9 more than the... (answered by prince_abubu)
When the digits of a two-digit number are reversed, the new number is 9 more than the... (answered by stanbon)
When the digits of a two-digit number are reversed, the new number is 9 more than the... (answered by ilana)
When the digits of a two-digit number are reversed, the new number is 9 more than the... (answered by ozymandias)
When the digits of a two-digit number are reversed, the new number is 9 more than the... (answered by idkweirdo)