Answer:
Kylie's grandfather is 73 years old.
Step-by-step explanation:
Let the first digit in Kylie's grandfather's age be x, which is the age of Isaac
Let the second digit in Kylie's grandfather's age be y, which is the age of Kendra.
Therefore from the given information we can say that
(10x + y) + x + y = 83
therefore 11x + 2y = 83
Let us take x = 7 then we get 77 + 2y = 83 y = 3
Therefore we can say Issac's age is 7
and Kendra's age is 3
and the age of Kylie's grandfather is 73.