[vc_row][vc_column][vc_column_text]The number B is obtained by removal of the last digit of the four-digit number A. Given A + B = 2003, find A.
[/vc_column_text][/vc_column][/vc_row][vc_row][vc_column][lvca_accordion][lvca_panel panel_title="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.)
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Problem Page Coordinator: Stephen Lee CMath MIMA - Mathematics in Education and Industry
Acknowledgement: The IMA are indebted to MEI for sourcing and supplying Mathematics Today with these well-known puzzles.
First published in Mathematics Today (December 2014)
