Practice Problems: Try to solve the following age problems: $1.)$ Edwin is $6$ years older than his brother Alvin. In two years, Edwin will be twenty more than one$-$third Alvin's age. How old are the brothers now? $2.)$ Alex is twice as old as his wife Riza. Five years ago, Alex was ten years younger than three times Riza's age. How old are they now? $3.)$ Olan is $3$ years older than his sister Mary. One$-$third of Olan's age is two years less than one$-$half his sister's age one year ago. Find their ages now.