Started out with 32/32. They ate 18/32, 32-18=14; 14/32. To simplify, 7/16 was left.
The answer to your question is Y
Let the triplets' age be x, the sister's age is then x-5.
product of their age as given
xÂł.(x-5)=75749+x+x+x+x-5
x^4 - 5xÂł= 4x +75744
x^4 - 5xÂł -4x -75744=0
resolving the equation,
we get
x = 18
therefore, Age of ben,bob and bill is 18
so , age of stephanie is x-5 = 18-5 = 13
stephanie is 13 years old.