SOLUTION: For how many positive, three-digit integers is one of the digits equal to the sum of the other two digits?

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Question 317208: For how many positive, three-digit integers is one of the digits equal to the sum of the other two digits?
Answer by JBarnum(2146)   (Show Source): You can put this solution on YOUR website!

112,121,211:1+1=2:makes 3 combos
123,132,231,213,321,312:1+2=3:makes 6 combos
134,143,314,341,413,431:1+3=4:makes 6 combos
145:6 combos
156:6 combos
167:6 combos
178:6 combos
189:6 combos


224:3 combos
235:6 combos
246:6 combos
257:6 combos
268:6 combos
279:6 combos


336:3 combos
347:6 combos
358:6 combos
369:6 combos


448:3 combos
459:6 combos
thats all possible since 4+6=10 and 5+5=10
=108 possible 3 digit numbers

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