If Leah is 6 years older than her sister, Sue, and John is 5 years older than Leah, and the total of their ages is 41. Then how old is Sue?

Let us assume the age of Sue = x years

Then

Age of Leah = x + 6

Age of John = 5 + (x + 6)

= x + 11

Total of their ages = 41

So

x + x + 6 + x + 11 = 41

3x + 17 = 41

3x = 41 - 17

3x = 24

x = 24/3

= 8 years

So Sue is 8 years old.

She is 30 years old.