CMAT 2013 Solved Question Paper

(d) Let one's and ten's digit be x and y, respectively.
Then, Number = 10y + x
From Statement I,
(10x + y) - (10y + x) = 9
⇒ x - y = 1
From Statement II, x + y = 7
From Statement III, x - y = 1
∴ Number can be found using Statements II and either I or III.