By drawing a line segment, we can know that after subtracting the age difference between the sister-in-law and the tortoise, the tortoise is five years old and the sister-in-law is the tortoise's current age; And if the age of the little turtle and her sister-in-law increases at the same time, her sister-in-law is 44 years old, and the little turtle is her sister-in-law's present age, it proves that the difference between five years old and 44 years old is exactly the same.

∴44-5=39

39÷3= 13

Age of Little Tortoise: 5+ 13= 18 (years)

Sister-in-law's age: 44- 13=3 1 (years old)

Grandma's age: 3 1×3=93 (years)

What do you think?