A First Course in Linear Algebra · Problem SSLE.C51
Systems of Linear Equations — Robert Beezer
Mathematics — Linear Algebra · solving-systems-of-linear-equations
Problem
Find all of the six-digit numbers in which the first digit is one less than the second, the third digit is half the second, the fourth digit is three times the third and the last two digits form a number that equals the sum of the fourth and fifth. The sum of all the digits is 24. (From The MENSA Puzzle Calendar for January 9, 2006.)