17

Part of 1996 Baltic Way

Problems(1)

Making the numbers A,B,C,D from the digits 1,2,3...9 once

Source: Baltic Way 1996 Q17

Using each of the eight digits

1,3,4,5,6,7,8

9

exactly once, a three-digit number

A

, two two-digit numbers

B

C

B<C

, and a one digit number

D

are formed. The numbers are such that

A+D=B+C=143

. In how many ways can this be done?

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