posted by MILDRED .
Could you please explain the quickest way to calculate these questions?
1)Julian's age has the same figures as his dad's with the digits reversed. The sum of their ages is 77 and Julian is 27 years younger than his dad. How old is Julian?
2) Amanda has 20 coins in her purse. She has only 10c,20c and 50c coins, and their total value is $5. If she has more 50c than 10c coins, how many 10c has she?
Let D = dad's age
let J = Julian's age.
Two equations. Two unknowns. Solve for D and J.