The sum of the digits of a two digit number is 9. If the digits are reversed, the new number if 63 greater than the original number. How do you find the original number.?

Question

19176 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2015-11-08T03:03:16

18

Let #x# be the ones digit
#=># The tens digit is #9 -x #

#10(9 - x) + x + 63= 10x + (9 - x)#

#=> 90 - 10x + x + 63 = 10x + 9 - x#

#=> 153 - 9x = 9x + 9#

#=> 153 - 9 = 18x#

#=> 144 = 18x#
#=> x = 8#

#=> 9 - x = 9 - 8 = 1#

Therefore, the number we are looking for is

#10(1) + 8 = 18#