Question 846790
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.