Age word problem

Question

Kate is 4 years older than her sister. The sum of their ages is 16. How old is kate?

Answer 1

kate has to be 10 because the sum the total of the 2 ages has to equal 16 and the only 2 number combinations that equal a set of numbers that are 4 more or 4 less then each other and combined equal a sum of 16 are 10 and 6.