Problema Solution
Six years ago, rob was half as old as his sister Robina. If Robina is d years old now, how old is robina.
Answer provided by our tutors
if the age of robina is d.
the age of rob is r
6 years ago her age was d-6
at that time rob was r-6
r-6=(d-6)/2
2r-12=d-6
2r=d+6
r=(d+6)/2