Let the two-digit number be 10a+b, where: - a= tens digit - b= units digit - ab=12 Possible digit pairs whose product is 12 : - (2,6)⟶ number =26 - (6,2)⟶62 - (3,4)⟶34 - (4,3)⟶43 Now apply the condition: If 36 is added, the digits interchange. Test each: - 26+36=62⟶ digits swapped ✓ - 34+36=70⟶ not swap x - 43+36=79⟶ not swap × - 62+36=98⟶ not swap × Only 26 works.