Question 369466
ONE-SIXTH OF A DENTIST'S AGE 8 YEARS AGO EQUALS ONE-TENTH OF HIS AGE 8 YEARS HENCE. WHAT IS HIS AGE NOW? 

Let x = the age of the dentist now

(x-8)/6 = (x+8)/10

Cross multiply
10(x-8) = 6(x+8)
10x-80  = 6x + 48
     4x = 128
      x = 32

The age of dentist now is 32 years old.