huda wrote:
Gene is 7 years older than Roberta. 6 years ago, Gene was twice as old as Roberta. What is Roberta’s current age?
Gene is 7 years older than Roberta.Let x = Roberta's PRESENT age
So, x + 7 = Gene's PRESENT age
6 years ago, Gene was twice as old as RobertaGiven their PRESENT ages (above) we can conclude that....
x - 6 = Roberta's age SIX YEARS AGO
So, x + 7 - 6 = Gene's age SIX YEARS AGO
Simplify: x + 1 = Gene's age SIX YEARS AGO
If Gene age was TWICE Roberta's age, we can write: x + 1 = 2(x - 6)
Expand: x + 1 = 2x - 12
Add 12 to both sides: x + 13 = 2x
Subtract x from both sides:
13 = x What is Roberta’s current age?x = Roberta's PRESENT age
So, Roberta's PRESENT age =
13 Answer: 13
Cheers,
Brent