Word Problem

[ECBERNA]

Can anyone help me with this problem.

In 3 years David will be twice as old as he was last year, How old is David now?

 

[blink]

x+3=2(x-1)
x+3=2x-2
x+5=2x
x+5-x =2x-x
5=x

So 5+3=8
5-1=4
He is 5

 

[soroban]

Hello, ECBERNA!

In 3 years David will be twice as old as he was last year.
How old is David now?

Set up some relations.

Let \(\displaystyle x\) = David's age now.

In 3 years, he will be 3 years older: .\(\displaystyle x+3\)

And last year, he was one year younger: .\(\displaystyle x-1\)


Now translate the English into Algebra:

. . \(\displaystyle \underbrace{\text{In 3 years}}_{x+3} \:\underbrace{\text{will be}}_{=}\: \underbrace{\text{twice}}_{2\:\times}\: \underbrace{\text{last year}}_{(x-1)}\)


There is our equation! .. . \(\displaystyle x + 3 \:=\:2(x-1)\)

Got it?