SOLUTION: In 3 years, Jeff will be twice as old as he was 4 years ago. How old is Jeff now?

Question 846790: In 3 years, Jeff will be twice as old as he was 4 years ago. How old is Jeff now?
Found 2 solutions by josh_jordan, jim_thompson5910:
Answer by josh_jordan(263) (Show Source): You can put this solution on YOUR website!
To solve, we need to set this word problem up as an equation. Let's break down each word (series of words):

In 3 years: + 3

Jeff: J

will be: =

twice as old as he was 4 years ago = 2(J - 4)

Now let's put all of this together:

J + 3 = 2(J - 4)

Now we have an equation we can solve. First, distribute the 2 to (J - 4):

J + 3 = 2J - 8

Subtract J from both sides of the equal sign:

J - J + 3 = 2J - J - 8 ----->

3 = J - 8

Finally, add 8 to both sides of the equal sign:

3 + 8 = J - 8 + 8 ----->

11 = J

Therefore, Jeff is 11 years old.

Answer by jim_thompson5910(35256) (Show Source): You can put this solution on YOUR website!
Let x = Jeff's current age right now

He is currently x years old

In 3 years, he will be x+3 years old.

Four years ago, he was x-4 years old.

-------------------------------------------------------

"In 3 years, Jeff will be twice as old as he was 4 years ago" means that

Solve for x to get...

Start with the given equation.

Distribute.

Subtract from both sides.

Subtract from both sides.

Combine like terms on the left side.

Combine like terms on the right side.

Divide both sides by to isolate .

Reduce.

----------------------------------------------------------------------

Answer:

So the solution is

This means that Jeff is currently 11 years old.

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