SOLUTION: sally is 3 times older that david in five years sally will be twice as old as david how old will sally be in 5 years

Question 56902: sally is 3 times older that david in five years sally will be twice as old as david how old will sally be in 5 years
Answer by askmemath(368) (Show Source): You can put this solution on YOUR website!
"sally is 3 times older that david"
Let David's present age = X
Then Sally's age = 3X
" in five years"
David's age = X+5
Sally's age = 3X+5
"sally will be twice as old as david"
3X+5 = 2(X+5)
Solving this
3X+5 = 2X+10
X = 5
Which means David's present age = 5
Sally's present age = 15
"how old will sally be in 5 years"
15+5 = 20 years
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