When three positive integers are added in pairs, the resulting sums are 998, 1050, and 1234. What is the difference between the largest and smallest of the three original positive integers?
A number or a short expression. Fractions can be typed as 3/2, and spacing doesn't matter.
Solution
Suppose that the three integers are x,y and z where x+y=998, x+z=1050, and y+z=1234. From the first two equations, (x+z)−(x+y)=1050−998 or z−y=52. Since z+y=1234 and z−y=52, then (z+y)+(z−y)=1234+52 or 2z=1286 and so z=643. Since z=643 and z−y=52, then y=z−52=643−52=591. Since x+y=998 and y=591, then x=998−y=998−591=407. The three original numbers are 407, 591, and 643. The difference between the largest and smallest of these integers is 643−407=236.
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