The number B is obtained by removal of the last digit of the four-digit number A. Given A + B = 2003, find A.
Reveal Solution
Let A = 10X + a. Then B = X. So 10X + a + X = 2003, or 11X + a = 2003. As ‘a’ must be single digit we can only have X = 182 and a = 1, so A = 1820+1 = 1821 (and B = 182).
(One could also write the initial equation as A = 10B+a directly, of course.)
