Let the triplets' age be x, the sister's age is then x-5.Â
product of their age as givenÂ
xÂł.(x-5)=75749+x+x+x+x-5
 x^4 - 5xÂł= 4x +75744
 x^4 - 5xÂł -4x -75744=0
 resolving the equation,
 we getÂ
 x = 18Â
 therefore, Age of ben,bob and bill is 18
 so , age of stephanie is x-5 = 18-5 = 13
 stephanie is 13 years old.